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Web Links lead you to sites on the World Wide Web with additional and current information about the topics studied in each chapter. The Web Links allow you to explore sites that show connections between what you are reading in the textbook and what is going on in the world around you. Astronomy is a rapidly changing field, with many exciting discoveries and new insights being made almost daily. No print textbook can keep pace with the new discoveries, and we hope the Web Links will provide you a good source of current information about our advancing knowledge of the universe. |
PART I Introducing Astronomy - Chapter: 1 | 2 | 3 | 4 | 5 | 6 |
PART II Planets and Moons - Chapter: 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 |
PART III Stars and Stellar Evolution - Chapter: 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 |
PART IV Galaxies and Cosmology - Chapter: 26 | 27 | 28 | 29 | 30 |
PART I Introducing Astronomy
Chapter 1: Astronomy and the Universe
Public Information about the Hubble Space Telescope - (Web Link 1-1) This site features an extensive gallery of astronomical images and animations,
plus information about the telescope itself.
ESA Hubble Site - (Web Link 1-1) This European Space Agency site has still more information about the Hubble Space
Telescope.
The Nine Planets - (Web Link 1-2) An overview of the history, mythology, and current scientific
knowledge of each of the planets and moons in our solar system. Each page has text
and images, some have sounds and movies, and most provide links to additional
information.
Views of the Solar System - (Web Link 1-2) An educational tour of the solar system, with images and information about
the Sun, planets, moons, asteroids, comets, and meteoroids.
The Nine Planets: The Sun - (Web Link 1-3) Information, images, and links to additional resources about the Sun.
Views of the Solar System: The Sun - (Web Link 1-3) This educational tour of the solar system has a page on the Sun with information,
images, animations, and links.
Solar Physics on the Web - (Web Link 1-3) An exhaustive and comprehensive list of all sorts of information about the Sun,
including images.
SEDS Messier Database: M42 - (Web Link1-4 ) Information about the Orion Nebula (M42 in the Messier catalog of deep-sky objects).
The Orion Nebula, M42 and M43 - (Web Link 1-4) Detailed information about the image in Figure 1-5, from the Anglo-Australian Observatory.
SEDS Messier Database: M1 - (Web Link 1-5) Information about the Crab Nebula (M1 in the Messier catalog of deep-sky objects).
The Crab Nebula Viewed by the VLT - (Web Link 1-5) Detailed information about the image in Figure 1-6, from the European Southern Observatory.
SEDS Messier Database: M1 - (Web Link 1-6) Information about the galaxy M100 (one of the Messier catalog of deep-sky objects).
Messier 100 (NGC 4321) in the Virgo cluster - (Web Link 1-6) Detailed information about the image in Figure 1-7, from the Anglo-Australian Observatory.
Astronomy Picture of the Day: Quasars - (Web Link 1-7) A list of images of quasars from the APOD archives.
HST Images of Quasars Quasar images from the Hubble Space Telescope. - (Web Link 1-7)
Hubble's 100,000th Exposure Captures Image Of Distant Quasar - (Web Link 1-7) Detailed information about the image in Figure 1-8, from the Hubble Space Telescope.
TOPEX/Poseidon: Understanding our Oceans & Climate from Space - (Web Link 1-8) The web site for the TOPEX/Poseidon satellite, which measures global sea level with
unparalleled accuracy.
Earth Observatory - (Web Link 1-8) An extensive NASA web site with a focus on Earth's climate and environmental change.
Chapter 2: Knowing the Heavens
Introduction to Archeoastronomy - (Web Link 2-1) Archeoastronomy is the study of the astronomical practices, celestial lore, mythologies, religions,
and world-views of ancient cultures. This site contains links to general resources on archeoastronomy,
Native American and Mesoamerican archeoastronomy, megalithic archeoastronomy (the study of sites such
as Stonehenge), and world archeoastronomy.
Valley City State University's Medicine Wheel - (Web Link 2-1) Information about a rock monument meant to capture some of the spirit and purpose
of the original Indian Medicine Wheels of North America.
Ancient Astronomy in Africa - (Web Link 2-1)
A web site for a course at the University of Texas on the astronomy of ancient Africa.
Ancient Greek Mathematics, Geography, and Astronomy - (Web Link 2-1) This site features items from the Library of Congress Vatican Exhibit.
The Constellations and their Stars - (Web Link 2-2) Includes lists of constellations and stars, interactive sky charts, Milky Way photos, and answers to frequently asked questions.
Anglo-Australian Observatory Images: Star Trails - (Web Link 2-3) Long-exposure images of the night sky, capturing the rotation of the Earth beneath the distant stars.
Historical Exhibits on Time and Timekeeping - (Web Link 2-4) An exhibit from the U.S. National Institute of Standards and Technology.
Time Service Department, U.S. Naval Observatory - (Web Link 2-4) This site features the USNO Master Clock, the standard of time for the United States.
World Time Zones - (Web Link 2-5) A detailed site with information about all the time zones on our planet.
This Week's Sky at a Glance - (Web Link 2-6) Gives viewing hints about current celestial events.
Alphabetical Listing of Constellations - (Web Link 2-7) A complete listing of all constellations, with links to further information, compiled
by Chris Dolan at the Univesity of Wisconsin.
Sunrise, Sunset, Moonrise, Moonset, and Twilight - (Web Link 2-8) Extensive tables of data from the U. S. Naval Obervatory.
Chapter 3: Eclipses and the Motion of the Moon
The Big Corona on August 11, 1999 - (Web Link 3-1) Detailed information about the Chapter 3 opening photo.
Fred Espenak's Eclipse Home Page - (Web Link 3-2) For everything you ever wanted to know about eclipses, past and present, see this site
maintained by Fred Espenak of NASA's Goddard Space Flight Center.
Chapter 4: Gravitation and the Waltz of the Planets
The Apollo Manned Space Program - (Web Link 4-1) The entire Apollo program is described in
detail at this site maintained by the National Air and Space Museum.
The Apollo Program - (Web Link 4-1) A NASA site with links to other Apollo program sites.
Occam's Razor - (Web Link 4-2) Information about the philosophical underpinnings of Occam's Razor, from the Principia Cybernetica Web.
William of Ockham - (Web Link 4-2) Biographical information from the University of Kent at Canterbury.
Yahoo: Nicolaus Copernicus - (Web Link 4-3) An extensive collection of links to information about Copernicus. The
Institute and Museum of the History of Science - (Web Link 4-4) in Florence, Italy, has a multimedia exhibition on
the life of Galileo, including images of his original telescope (and of the preserved middle finger
of his right hand!). Biographies of Copernicus, Tycho, Kepler, and other important figures in the history
of astronomy can also be found at this site. Galileo Project - (Web Link 4-4) This web site at Rice University has a wealth of information about Galileo's life and times. The site even
includes directions for making a telescope like Galileo's using inexpensive materials.
Yahoo: Galileo Galilei - (Web Link 4-4) An extensive collection of links to information about Galileo.
Yahoo: Tycho Brahe - (Web Link 4-5) An extensive collection of links to information about Tycho.
Yahoo: Johannes Kepler - (Web Link 4-6) An extensive collection of links to information about Kepler. A web site hosted by the European Laboratory for Particle Physics, is a collection of material about Sir Isaac Newton.
Yahoo: Isaac Newton - (Web Link 4-7) An extensive collection of links to information about Newton.
On-line primer on spacecraft navigation - (Web Link 4-8) Newton's laws and the law of universal gravitation are the principles by which spacecraft navigate through our
solar system. This NASA Jet Propulsion Laboratory site is an excellent on-line primer on spacecraft navigation.
Views of the Solar System: Comets - (Web Link 4-9)
A page on comets from an educational tour of the solar system.
A Bird's Eye View of a Galaxy Collision - (Web Link 4-10)
An image of interacting galaxies from the Hubble Space Telescope.
Galactic Silhouettes - (Web Link 4-10)
An image of interacting galaxies from the Hubble Space Telescope.
A Grazing Encounter Between Two Spiral Galaxies - (Web Link 4-10)
An image of interacting galaxies from the Hubble Space Telescope.
Hubble Reveals Stellar Fireworks Accompanying Galaxy Collisions - (Web Link 4-10)
An image of interacting galaxies from the Hubble Space Telescope.
Chapter 5: The Nature of Light
How the Radio Spectrum Works - (Web Link 5-2) An explanation of how different radio frequencies are allocated for different broadcast purposes.
How Thermometers Work - (Web Link 5-3) An explanation of how temperature is measured.
About Temperature - (Web Link 5-3) A description of how our understanding of temperature has evolved over the centuries.
The Discovery of the Electron - (Web Link 5-4), the first of the basic constituents of matter to be identified, is the
subject of a web site at the American Institute of Physics.
Einstein: Image and Impact - (Web Link 5-5) A unique site of Einstein information, including photographs and audio clips, hosted by
the American Institute of Physics.
Detailed information about the image in Figure 5-16, from the Hubble Space Telescope.
WebElements Periodic Table - (Web Link 5-7)
An award-winning web site with information about the periodic table and the chemical elements.
The Comic Book Periodic Table of the Elements - (Web Link 5-7)
An entertaining and informative look at the chemical elements, from the University of Kentucky.Biography of Niels Bohr - (Web Link 5-8)
Information about the life and work of the Nobel Prize-winning physicist.
Chapter 6: Optics and Telescopes
The
Mauna Kea Observatories - (Web Link 6-1) are located near the summit of Mauna Kea on the island of Hawaii.
Hobby-Eberly Telescope - (Web Link 6-2) This 11-m reflecting telescope is dedicated to spectroscopic observations.
W. M. Keck Observatory - (Web Link 6-2) Home of the Keck I and Keck II 10-m telescopes.
The Large Binocular Telescope - (Web Link 6-2) The goal of the LBT project is to construct a binocular telescope consisting of two 8.4-meter mirrors on a common mount.
Subaru Telescope - (Web Link 6-2) The Subaru Telescope is an 8.3 meter optical-infrared telescope at the summit of Mauna Kea, Hawaii, operated by the National
Astronomical Observatory of Japan.
ESO Very Large Telescope (VLT) - (Web Link 6-2) at the Paranal Observatory (Atacama, Chile) will be the world's largest
and most advanced optical telescope. It comprises four 8.2-meter reflecting Unit Telescopes and several
moving 1.8-meter Auxiliary Telescopes, the light beams of which can be combined in the VLT Interferometer
(VLTI). With its unprecedented optical resolution and unsurpassed surface area, the VLT produces
extremely sharp images and can record light from the faintest and most remote objects in the universe.
Information and images can be found at this web site. The Gemini Project - (Web Link 6-2) is an international
partnership to build two 8-meter telescopes, one on Mauna Kea, Hawaii, and one on Cerro Pachon, Chile.
W. M. Keck Observatory - (Web Link 6-3) Home of the Keck I and Keck II 10-m telescopes.
Center for Adaptive Optics - (Web Link 6-4) This web site from the University of California, Santa Cruz has a wealth of information about adaptive optics, including images.
Introduction to Adaptive Optics - (Web Link 6-4) This short article explains the fundamental principles of adaptive optics.
Adaptive Optics Links - (Web Link 6-4) An extensive collection of links to information about
adaptive optics and how it is applied at various observatories.
ESO Very Large Telescope (VLT) - (Web Link 6-5) at the Paranal Observatory (Atacama, Chile) will be the world's largest
and most advanced optical telescope. It comprises four 8.2-meter reflecting Unit Telescopes and several
moving 1.8-meter Auxiliary Telescopes, the light beams of which can be combined in the VLT Interferometer
(VLTI). With its unprecedented optical resolution and unsurpassed surface area, the VLT produces
extremely sharp images and can record light from the faintest and most remote objects in the universe.
Information and images can be found at this web site. International Dark-Sky Association - (Web Link 6-6) The International Dark-Sky Association is devoted to combatting light pollution.
How Digital Cameras Work - (Web Link 6-7) The CCD detectors used in astronomy operate on
the same basic principles as those in digital cameras.
Very Large Array - (Web Link 6-8) VLA is one of the world's premiere astronomical radio observatories. It consists of 27 antennas
arranged in a huge Y pattern up to 36 kilometers (22 miles) across.
Very Long Baseline Array - (Web Link 6-9) VLBA operated by the National Radio Astronomy Observatory (NRAO), is an array of ten 25-meter
antennas distributed over U.S. territory.
Introduction to Infrared Astronomy - (Web Link 6-10) A tutorial from the Infrared Processing and
Analysis Center at the California Institute of Technology.
Space Infrared Telescope Facility (SIRTF) - (Web Link 6-11) This 85-cm infrared telescope is
scheduled to be placed in orbit in 2002.
Far Infrared Spectroscopic Explorer (FUSE) - (Web Link 6-12) FUSE is an orbiting observatory that does high-resolution spectroscopy at the far-ultraviolet wavelengths.
Hubble Space Telescope (HST) - (Web Link 6-13) The Space Telescope Science Institute (STScI) maintains the main web site for information
about Hubble. The
Next Generation Space Telescope - (Web Link 6-14) is the planned successor to the Hubble Space Telescope.
High-Energy Astronomical Observations - (Web Link 6-15) NASA's High Energy Astrophysics
Science Archive Research Center (HEASARC) is the repository for data from all
orbiting telescopes that detect high-energy photons (gamma-ray, X-ray, and extreme
ultraviolet).
Chandra X-Ray Observatory Center (CXC) - (Web Link 6-16) The orbiting Chandra X-ray Observatory is recording images of the sky at X-ray
wavelengths with unprecedented resolution. XMM-Newton, a project of the European Space Agency, is an orbiting observatory
able to detect extremely faint X-ray sources.
Compton Gamma-ray Observatory (CGRO) - (Web Link 6-17) During its nine years of operation,
CGRO scanned the sky at gamma-ray wavelengths and made a number of important
discoveries about energetic processes in the universe.
Multiwavelength All-Sky Images - (Web Link 6-18) This web site depicts the entire sky at
wavelengths from radio to gamma-ray.
PART II Planets and Moons
Chapter 7: Our Solar System
Astronomy Picture of the Day: The Ecliptic Plane - (Web Link 7-1) Detailed information about
the image that opens Chapter 7, from the APOD archives.
Images from Clementine - (Web Link 7-1) The Clementine spacecraft mapped the Moon in four
wavelength bands over the period February through May 1994. This site displays
some of the finest Clementine images.
The Nine Planets: A Multimedia Tour of the Solar System - (Web Link 7-2) Well-illustrated, with many links.
Views of the Solar System - (Web Link 7-2) An educational tour of the solar system, with images and information about the Sun,
planets, moons, asteroids, comets, and meteoroids.
Planetary Science Research Discoveries - (Web Link 7-2) This educational site shares the
latest research on planets, meteorites, and other solar system bodies being made by
NASA-sponsored scientists.
Titan - What We Know - (Web Link 7-4) A summary of current knowledge from the web site for
the Cassini mission, which plans to land a spacecraft on Titan in 2004.
Galileo Project: Europa - (Web Link 7-5) A summary of current knowledge from the web site for
the Galileo spacecraft, which has been observing Europa and the other Jovian
satellites since 1995.
Hubble Views Ancient Storm in the Atmosphere of Jupiter - (Web Link 7-6) Detailed information about the image in Figure 7-5, from the Hubble Space Telescope.
A Closer Encounter With Mars - (Web Link 7-7) Detailed information about the image in Figure
7-6, from the Hubble Space Telescope.
NEAR Shoemaker - (Web Link 7-8) In 2000 the NEAR Shoemaker spacecraft went into orbit
around the asteroid 433 Eros. The spacecraft web site has a wealth of data,
including images and movies, about this asteroid.
Glimpses into Eros' shadows - (Web Link 7-8) Detailed information about the image in Figure 7-7, from the NEAR Shoemaker spacecraft.
Comet Hale-Bopp - (Web Link 7-9) This NASA web site has links to more than 5,000 images of
Comet Hale-Bopp, the great comet of 1997.
Images and Spectra of Comet Hale-Bopp - (Web Link 7-9) Views of the comet made by University of Hawaii astronomers.
Cosmology Tutorial - (Web Link 7-10) Professor Ned Wright at UC-Los Angeles maintains this
excellent online cosmology tutorial, including information about the Big Bang.
The Nebula around Antares - (Web Link 7-11) Detailed information about the image in Figure 7-9, from the Anglo-Australian Observatory.
Stars: Antares - (Web Link 7-11) From the extensive "Stars" web site of Professor James Kaler at
the University of Illinois.
Reflection Nebula in Orion, NGC 1973-1975-1977 - (Web Link 7-12) Detailed information about the image in Figure 7-10, from the Anglo-Australian Observatory.
SEDS Messier Database: M42 - (Web Link 7-13) Information about the Orion Nebula (M42 in the
Messier catalog of deep-sky objects).
Hubble Picture Adds to Planet-Making Recipe - (Web Link 7-13) An image of a disk surrounding a young star, from the Hubble Space Telescope.
Vast Stellar Disks Set Stage for Planet Birth - (Web Link 7-13) Images of disks surrounding
young stars, from the Hubble Space Telescope.
Dust Disks Around Young Stars - (Web Link 7-13) Images of possible planet formation, from the
Hubble Space Telescope.
A Twist In A Suspected Protoplanetary Disk - (Web Link 7-13) An image of a disk surrounding a
young star, from the Hubble Space Telescope. This web site from Washington University in St. Louis gives an
introduction to cosmic dust particles and what we can learn from them.
Dry Droplets of Fiery Rain - (Web Link 7-15) This article by G. Jeffrey Taylor describes an
experiment to test one model of how chondrules form.
The Birth of Stars - (Web Link 7-16) This NASA web site describes our present understanding of how stars are formed.
Hubble Observes the Fire and Fury of a Stellar Birth - (Web Link 7-16) Detailed information
about the image in Figure 7-19a, from the Hubble Space Telescope.
The Stars in the Trifid Nebula - (Web Link 7-16) Detailed information about the image in Figure
7-19b, from the Anglo-Australian Observatory.
SEDS Messier Database: M20 - (Web Link 7-16) Information about the Trifid Nebula (M20 in the
Messier catalog of deep-sky objects).
The Extrasolar Planets Encyclopaedia - (Web Link 7-17) An up-to-date list of all of the known
extrasolar planets.
The Extrasolar Planet Search - (Web Link 7-17) This web site from Professor Geoff Marcy's group
includes the latest results from the search for planets orbiting other stars. It also
describes in detail the techniques used for detecting such planets.
Planet Hunters on Trail of Worlds Smaller than Saturn - (Web Link 7-17) In 2000 astronomers detected the first extrasolar planet with a mass that is probably less than that of
Saturn.
The Discovery of Brown Dwarfs - (Web Link 7-18) This Scientific American article by Professor
Gibor Basri of the University of California, Berkeley explains our present knowledge
of these "failed stars."
First Clear Evidence for Existence of a Brown Dwarf - (Web Link 7-18) Detailed information about the image in Figure 7-22, from the Hubble Space Telescope.
Observations of Young Brown Dwarfs - (Web Link 7-18) In 2000 the Very Large Telescope
observed a brown dwarf companion of a young, nearby star.
Chapter 8: Our Living Earth
Blue Marble 2000 - (Web Link 8-1) Detailed information about the image that opens Chapter 8,
from NASA's Goddard Space Flight Center. Space shuttle astronauts have taken a tremendous number of photographs of the Earth's surface from orbit, and you can search an extensive collection at this site.
The Nine Planets: Earth - (Web Link 8-2) An overview of the history, mythology, and current scientific knowledge of Earth.
Views of the Solar System: Earth - (Web Link 8-2) An educational tour of the solar system. The page on Earth includes many informative articles, images, animations, and links to more information.
Understanding Earth - (Web Link 8-2) Understanding Earth is a leading textbook on geology by Frank Press and
Raymond Siever. The web site that accompanies the book has a wealth of
information about the Earth.
Earthquake Information from the USGS - (Web Link 8-3) This is the place to find the most up-to-date earthquake information.
This Dynamic Earth: The Story of Plate Tectonics - (Web Link 8-4) W. J. Kious and R. I. Tilling. An excellent introduction to plate tectonics from the U.S. Geological Survey (USGS). The text and graphics explain the history of plate tectonics (and the colorful characters behind the theory), as well as the latest research.
Seafloor Spreading - (Web Link 8-5) This section of "This Dynamic Earth" by W. J. Kious and R. I.
Tilling describes how seafloor spreading was discovered. An important mission of USGS is to maintain a network of volcano observatories at geologically active sites within the United States. From their volcano web page, you can get up-to-the-minute updates on volcanic activity. The
Electronic Volcano - (Web Link 8-6) at Dartmouth College is another excellent starting point for volcano information.
Volcano World - (Web Link 8-6) This site from the University of North Dakota has detailed
information about volcanoes of all kinds.
Earth Observatory - (Web Link 8-8) Earth Observatory provides up-to-date satellite imagery and scientific
information about our home planet. The focus is on Earth's climate and
environmental change.
What is El Niño? - (Web Link 8-9) This article by David Herring discusses the origin and
significance of the El Niño phenomenon. This reference article explains the cold counterpart of El Niño, called La
Niña.
U. S. Environmental Protection Agency: Global Warming - (Web Link 8-11) This comprehensive site provides an introduction to global warming, its causes, and what can be done to
control it.
Spotlight: Climate Change - (Web Link 8-11) This web site from the U. S. State Department
describes national and international efforts to reduce greenhouse gas emissions.
The Ozone Hole Tour - (Web Link 8-12) An extensive tutorial about all aspects of the Antarctic
ozone hole, provided by Cambridge University.
British Antarctic Survey Ozone Measurements - (Web Link 8-12) This site presents up-to-date data about ozone levels over Antarctica.
U.S. Environmental Protection Agency: Ozone Depletion - (Web Link 8-12) This web site
contains information about the science of ozone depletion, as well as government
regulations designed to preserve atmospheric ozone.
Chapter 9: Our Barren Moon
This web site has information about the last manned mission to the
Moon.
The Nine Planets: The Moon - (Web Link 9-2) An overview of the history, mythology, and current scientific knowledge of Earth's Moon. Lots of images and links.
Views of the Solar System: The Moon - (Web Link 9-2) An educational tour of the solar system. The page on the Moon includes many informative articles, images, animations, and links to more information.
Planetary Science Research Discoveries: The Moon - (Web Link 9-2) A collection of articles about recent lunar research
Touring the Moon with Binoculars - (Web Link 9-3) Information from Sky & Telescope about how
best to observe the Moon with inexpensive equipment.
Lunar Information for Amateur Astronomers - (Web Link 9-3) An extensive collection of links
with information about viewing the Moon.
Virtual Reality Moon Phase Pictures - (Web Link 9-3) This site allows you to se the phase of the
Moon at any time on any date.
Earth and Moon Viewer - (Web Link 9-3) A wonderful interactive tool that lets you view the Moon from the Sun, the Earth, or the far side; above named surface features or spacecraft landing sites; or as a map showing night and day.
Lunar Impact Crater Geology and Structure - (Web Link 9-4) This site explains how impacts give rise to the characteristic shapes of lunar craters.
The Lunar Far Side from Luna 3 - (Web Link 9-5) A collection of images from the first spacecraft to view the far side of the Moon.
Exploring the Moon - (Web Link 9-6) An extensive web site about lunar exploration from the Lunar and Planetary Institute.
NSSDC Lunar Image Catalog - (Web Link 9-6) This page has links to images from all lunar missions to date.
NSSDC Lunar Exploration - (Web Link 9-6) Links to information about various lunar missions,
from the U. S. National Space Science Data Center.
Ranger: Mission to the Moon - (Web Link 9-6) This NASA web site details the Ranger program.
Surveyor Moon Landers - (Web Link 9-6) This NASA web site describes the Surveyor series of
spacecraft.
Apollo Lunar Surface Journal - (Web Link 9-7) This site allows you to follow in the footsteps of
the Apollo astronauts as they explore the surface of the Moon.
The Apollo Program - (Web Link 9-7) A NASA site with links to other Apollo program sites. Clementine Project Information - (Web Link 9-8) Many links to information about the unmanned Clementine lunar explorer.
Lunar Prospector - (Web Link 9-9) Information about the unmanned explorations of the Moon by Lunar Prospector.
The Moon at its Core - (Web Link 9-10) This article by Linda M. V. Martel describes the evidence
for the existence of a lunar core.
Rocks and Soils from the Moon - (Web Link 9-11) This web site from the Johnson Space Flight
Center describes their extensive collection of lunar rocks.
Chapter 10: Sun-Scorched Mercury
Global Mosaic of Mercury - (Web Link 10-1) Detailed information about the image that opens
Chapter 10, from the U. S. National Space Science Data Center.
The Nine Planets: Mercury - (Web Link 10-2) An overview of the history and current scientific knowledge of Mercury. Lots of images and links.
Views of the Solar System: Mercury - (Web Link 10-2)
An educational tour of the solar system. The page on Mercury includes many informative articles, images, animations, and links to more information.
Mercury on the Horizon - (Web Link 10-3) A web page with useful information about viewing Mercury.
Arecibo Observatory - (Web Link 10-4) The Arecibo Observatory is part of the National
Astronomy and Ionosphere Center, which is operated by Cornell University under a
cooperative agreement with the National Science Foundation. This web page from the U. S. National Space Science Data Center has
information and links about this pioneering mission to Mercury.
Ice on Mercury - (Web Link 10-6) This web page describes the arguments for and against the
existence of water ice on Mercury, as well as suggesting how ice could have gotten
there.
The Discovery of Water Ice on Mercury - (Web Link 10-6) A web site from the National Radio
Astronomy Observatory describes how radio astronomers first found evidence for
water ice at Mercury's poles. "Mercury Unveiled" - (Web Link 10-6) University of Hawaii, Planetary Science Research Discoveries. Although there have been no new space missions to Mercury since Mariner 10, the wealth of data returned by that spacecraft is still being analyzed by scientists. Some recent results are discussed here.
MESSENGER Mission to Mercury - (Web Link 10-7) This planned mission is scheduled for launch in 2004. The spacecraft will fly by Venus in 2006 and 2007, fly by Mercury in 2008, and enter orbit around Mercury in 2009. The mission will collect data on Mercury's atmosphere; core, crust, and mantle; and magnetosphere.
ISAS Mercury Orbiter - (Web Link 10-7) A proposed mission to study Mercury's interior, surface,
and magnetosphere with an unmanned spacecraft that would arrive in Mercury orbit
in 2009.
Bepi Colombo - (Web Link 10-7) This ambitious European mission to Mercury will deliver two
orbiters and a lander to Mercury.
Chapter 11: Cloud-Covered Venus
The Nine Planets: Pictures of Venus - (Web Link 11-1) An extensive collection of links to images
and movies of Venus.
The Nine Planets: Venus - (Web Link 11-2) An overview of the history and current scientific knowledge of Venus. Lots of images and links.
Views of the Solar System: Venus - (Web Link 11-2) An educational tour of the solar system. The page on Venus includes many informative articles, images, animations, and links to more information. Detailed information about the first spacecraft from Earth to fly past
another planet.
Mariner 2 Mission to Venus - (Web Link 11-3) Summary of the Mariner 2 Mission to Venus
Venus Missions - (Web Link 11-4) A comprehensive list of all attempted missions to Venus, with
information about each.
Volcano World - (Web Link 11-5) This site from the University of North Dakota has detailed
information about volcanoes of all kinds, including Mt. St. Helens.
"Hotspots": Mantle Thermal Plumes - (Web Link 11-6) This section of "This Dynamic Earth" by
W. J. Kious and R. I. Tilling describes how hot-spot volcanoes on Earth can form in
the middle of a tectonic plate.
Volcanoes on Venus - (Web Link 11-6)
From Volcano World at the University of North Dakota.
NASA Jet Propulsion Laboratory's
Magellan Mission to Venus - (Web Link 11-7)
The NSSDC Photo Gallery: Venus - (Web Link 11-7)
An extensive collection of Venus images.
The Magellan Image Browser - (Web Link 11-7)
Massachusetts Institute of Technology
The Face of Venus - (Web Link 11-8)
The site includes hypertext documents and interactive databases of surface features, such as an atlas of coronae and an atlas of craters.
Chapter 12: Red Planet Mars
Hubble Space Telescope Images of Mars - (Web Link 12-1) A catalog of images of Mars from the
Hubble Space Telescope.
The Nine Planets: Mars - (Web Link 12-2) An overview of the history and current scientific knowledge of Mars. Lots of images and links.
Views of the Solar System: Mars - (Web Link 12-2) An educational tour of the solar system. The page on Mars includes many informative articles, images, animations, and links to more information.
History of Mars Exploration: - (Web Link 12-3) The story of how our understanding of Mars have
evolved from ancient Babylonia down to the present day.
The Planet Mars: A History of Observation and Discovery - (Web Link 12-3) Online version of William Sheehan's excellent history of Martian exploration.
Chronology of Mars Exploration - (Web Link 12-4) Links to all attempted missions to the red
planet since 1960.
Viking Orbiter 1 - (Web Link 12-5) U. S. National Space Science Data Center
Viking Orbiter 2 - (Web Link 12-5) U. S. National Space Science Data Center
Malin Space Science Systems - (Web Link 12-5) built and operates the Mars Orbiter Camera on board Mars Global Surveyor. Their web site has
tens of thousands of images from that mission.
Measuring the Topography of Mars - (Web Link 12-6) This web site describes how MOLA, the
Mars Orbiter Laser Altimeter on board Mars Global Surveyor, reveals the
topography of the Martian surface with unprecedented accuracy. There are many
links to maps of the surface.
MOC Images Suggest Recent Sources of Liquid Water on Mars - (Web Link 12-7) Observations from Mars Global Surveyor suggest that liquid water has existed on the Martian
surface in the very recent past.
Mars Surprise - (Web Link 12-7) This NASA web page explores the idea that young channels on
Mars may be due to the release of subsurface water.
Global Climatic Change on Mars - (Web Link 12-8) An article by Jeffrey S. Kargel and Robert G.
Strom about the evolution of the Martian climate. From the November 1996 issue of
Scientific American.
Viking Landers - (Web Link 12-9) Links to the full story of the Viking 1 and Viking 2 landers and
the discoveries they made.
On Mars: Exploration of the Red Planet 1958-1978 - (Web Link 12-9) The official NASA history, with emphasis on the Viking missions.
NASM Space Artifacts: Viking - (Web Link 12-10) About the Smithsonian National Air and Space Museum's Viking Lander.
Martian Dust Devils - (Web Link 12-11) Mars Global Surveyor has imaged the daily appearance of
dust devils on the Martian surface.
NASA Mars Exploration Program - (Web Link 12-13) This web site has complete information
about current and future NASA misions to Mars.
Mars Express - (Web Link 12-13) This ESA web site describes the first European mission to Mars. The British-led effort to place a lander on Mars as part of the
European Space Agency's Mars Express mission to be launched in June 2003. Page at the National Space Science Data Center. The Japanese spacecraft Nozomi was launched toward Mars on July 3, 1998. It was originally scheduled to reach Mars in October 1999, but its arrival has been delayed four years to conserve fuel. When it enters Martian orbit in December 2003, it will devote most of its observations to studies of the planet's atmosphere and magnetic field.
Chapter 13: Jupiter: Lord of the Planets
Cassini Images of Jupiter - (Web Link 13-1) While en route to Saturn for a 2004 arrival, the
Cassini spacecraft made a close approach to Jupiter. This web site has an extensive
collection of images and animations from this encounter.
The Nine Planets: Jupiter - (Web Link 13-2) An overview of the history and current scientific knowledge of Jupiter. Lots of images and links.
Cassini Jupiter Encounter - (Web Link 13-3)
Full details about observations of Jupiter by the Cassini spacecraft during 2000-01.
Links to images and resources on Jupiter and Jupiter missions; frequently asked questions about Jupiter.
A False Color Mosaic of the Great Red Spot - (Web Link 13-4)
Detailed information about the image in Figure 13-6, from the Galileo spacecraft.
Galileo Views the Great Red Spot - (Web Link 13-4)
A collection of images of the Great Red Spot recorded by the Galileo spacecraft.
Galileo Views the Jovian Atmosphere - (Web Link 13-5)
A collection of images of atmospheric phenomena on Jupiter recorded by the Galileo spacecraft.
Comet Shoemaker-Levy 9 Collision with Jupiter - (Web Link 13-7)
Views of the Solar System: Shoemaker-Levy 9/Jupiter Impact - (Web Link 13-7)
Metallic Hydrogen - (Web Link 13-9)
This article from the Lawrence Livermore National Laboratory describes high-pressure experiments that have produced liquid metallic hydrogen here on Earth.
Jupiter's Interior and Magnetosphere - (Web Link 13-10)
Information on Galileo findings about Jupiter's internal structure and magnetic environment.
Transit Times of Jupiter's Great Red Spot - (Web Link 13-12)
This page from the Sky & Telescope web site gives the best times to observe the Great Red Spot with a telescope.
Chapter 14: The Galilean Satellites of Jupiter
Views of the Solar System: The Discovery of the Galilean Satellites - (Web Link 14-1)
The Nine Planets: Io - (Web Link 14-2) Information, images, and links to additional resources about Io.
The Nine Planets: Europa - (Web Link 14-2) Information, images, and links to additional resources about Europa.
The Nine Planets: Callisto - (Web Link 14-2) Information, images, and links to additional resources about Callisto.
Galileo Observes Io - (Web Link 14-4) A summary of Galileo observations of Io.
An Arizona-Sized Eruption on Io - (Web Link 14-5) Detailed information about the image in
Figure 14-6, from the Galileo spacecraft.
Volcanic Activity on Io - (Web Link 14-5) A collection of Galileo images of plumes, calderas, and flows on Io.
Eruption at Tvashtar Catena - (Web Link 14-6) Detailed information about the image in Figure 14-7, from the Galileo spacecraft.
Hot Spots on Io - (Web Link 14-7) Detailed information about the image in Figure 14-8, from the
Galileo spacecraft.
Io: Eclipse and Night Side - (Web Link 14-7) A collection of Galileo images made when Io is in
Jupiter's shadow and also of the night side of Io. These images reveal high-
temperature hot spots and diffuse atmospheric and plume glows.
Galileo Observes Europa - (Web Link 14-8) A summary of Galileo observations of Europa.
Ridges and Fractured Terrain on Europa - (Web Link 14-9) A collection of Galileo images of Europa's fractured surface.
Chaotic Terrain on Europa - (Web Link 14-10) A collection of Galileo images of Europa's ice rafts
and other chaotic terrain.
Galileo Observes Ganymede - (Web Link 14-11) A summary of Galileo observations of Ganymede.
Dark Terrain on Ganymede - (Web Link 14-12) A collection of Galileo images of Ganymede's dark terrain.
Bright Terrain on Ganymede - (Web Link 14-13) A collection of Galileo images of Ganymede's
bright terrain.
Galileo Observes Callisto - (Web Link 14-14) A summary of Galileo observations of Callisto.
Galileo: Jupiter's Inner Satellites and Rings - (Web Link 14-15)
Best images yet of Thebe, Amalthea and Metis Galileo - (Web Link 14-15) recorded the highest-resolution images ever obtained of these small, irregularly shaped satellites.
Galileo: Jupiter's Inner Satellites and Rings - (Web Link 14-16)
The Story of Jupiter's Rings - (Web Link 14-16) This web page has an extensive collection of
images and diagrams of all aspects of Jupiter's rings.
Jupiter's Main Ring and Halo - (Web Link 14-16) Detailed information about the image in Figure
14-20, from the Galileo spacecraft.
Jupiter's Outer Satellites - (Web Link 14-17) Information about the small moons of Jupiter that
orbit outside Callisto, the outermost of the Galilean satellites.
Jupiter's New Moon - (Web Link 14-17) Information about S/1999 J1, the newest Jovian satellite to
be discovered.
Chapter 15: The Spectacular Saturnian System
Hubble Provides Clear Images Of Saturn's Aurora - (Web Link 15-1) Detailed information about the image that opens Chapter 15, from the Hubble Space Telescope.
The Nine Planets: Saturn - (Web Link 15-2) Information, images, and links to additional resources about Saturn and its satellites.
Views of the Solar System: Saturn - (Web Link 15-2) An educational tour of the solar system. The page on Saturn includes information, images, animations, and links to more information on Saturn, Saturn's rings, and the Cassini mission. Also includes links to Views of the Solar System pages for each of Saturn's moons.
Saturn's Rings - (Web Link 15-3) A gallery of images made by the Hubble Space Telescope.
Historical Background of Saturn's Rings - (Web Link 15-4) The story of how our understanding of
Saturn's rings has evolved since their discovery in 1610.
Saturn's Ring System - (Web Link 15-5) A collection of images and animations of the rings of
Saturn, from the two Voyager spacecraft. An artist's impression of the view from one of the two shepherd
satellites of Saturn's F ring.
Saturn in Natural Colors - (Web Link 15-7) Detailed information about Figure 15-11, from the
Hubble Space Telescope.
Metallic Hydrogen - (Web Link 15-8) This article from the Lawrence Livermore National Laboratory
describes high-pressure experiments that have produced liquid metallic hydrogen
here on Earth.
The Nine Planets: Titan - (Web Link 15-9) Information, images, and links to additional resources about Titan, Saturn's largest satellite.
Near-Infrared Images of Titan's Surface - (Web Link 15-10) Using the 10-m Keck telescope with a
technique called speckle interferometry, astronomers have been able to map details
on the surface of Saturn's largest satellite.
Hubble Observes the Surface of Titan - (Web Link 15-10) This page shows details on Titan's
surface observed at near-infrared wavelengths by the Hubble Space Telescope. The European Space Agency's web site. Huygens is the Titan probe being carried to the Saturn system by Cassini.
Chapter 16: The Outer Worlds
Astronomy Picture of the Day: Uranus - (Web Link 16-1) A list of images of Uranus and its moons from the APOD archives.
Astronomy Picture of the Day: Neptune - (Web Link 16-1) A list of images of Neptune and its moons from the APOD archives.
Astronomy Picture of the Day: Pluto - (Web Link 16-1) A list of images of Pluto and Charon from the APOD archives.
The Nine Planets: Uranus - (Web Link 16-2) Information, images, and links to additional resources about Uranus and its satellites.
Views of the Solar System: Uranus - (Web Link 16-2) An educational tour of the solar system. The page on Uranus includes information, images, animations,
and links to more information on Uranus and Uranus's rings. Also includes links to Views of the Solar
System pages for each of Uranus's moons.
Hubble Space Telescope: Uranus - (Web Link 16-2) A catalog of images of Uranus from the Hubble Space Telescope.
The Nine Planets: Neptune - (Web Link 16-3) Information, images, and links to additional resources about Neptune and its satellites.
Views of the Solar System: Neptune - (Web Link 16-3) The page on Neptune includes information, images, animations, and links to more information on
Neptune and Neptune's rings. Also includes links to Views of the Solar System pages for each of
Neptune's moons.
Hubble Space Telescope: Neptune - (Web Link 16-3) A catalog of images of Neptune from the Hubble Space Telescope.
The Voyager Project: Uranus images - (Web Link 16-4) A collection of images of Uranus and its
satellites from the Voyager 2 spacecraft.
Hubble finds many bright clouds on Uranus - (Web Link 16-5) New Hubble Space Telescope images show 20 clouds in the atmosphere of Uranus—nearly
as many clouds as the previous total in the history of modern observations of the planet. The
images also provide new insights into the dynamics of the Uranian rings.
Hubble Space Telescope movie of Uranus and its rotation - (Web Link 16-6) A dramatic time-lapse movie by the Hubble Space Telescope shows for the first time seasonal
changes on Uranus.
Hubble Provides A Moving Look At Neptune's Stormy Disposition - (Web Link 16-7) Simultaneous observations of Neptune made with the Hubble Space Telescope and
NASA's Infrared Telescope Facility on Mauna Kea reveal Neptune's dynamic
weather systems.
The Uranian Ring System - (Web Link 16-8) Information about Uranus's rings from NASA's Ames Research Center.
Neptune's Ring System - (Web Link 16-9) Information about the rings of Neptune from NASA's
Ames Research Center.
Hubble Tracks Uranus's Clouds and Satellites - (Web Link 16-10) Enhanced Hubble Space
Telescope images reveal the motion of Uranus's smaller satellites.
The Struggles to Find the Ninth Planet - (Web Link 16-11) Clyde Tombaugh's reminiscences about his discovery of Pluto.
The Nine Planets: Pluto - (Web Link 16-12) Information, images, and links to additional resources about Pluto and its moon, Charon.
Views of the Solar System: Pluto - (Web Link 16-12) The page on Pluto includes information, images, animations, and links to more
information on Pluto and Charon.
Chapter 17: Vagabonds of the Solar System
Historical Comet Observations - (Web Link 17-1) This article describes sightings of important comets throughout history. It shows a portion of the eleventh-century Bayeux
Tapestry that depicts Comet Halley on April 24, 1066.
The Nine Planets: Small Bodies - (Web Link 17-2) Brief article with links to many other additional resources on asteroids, meteoroids, and comets.
Minor Planet Center - (Web Link 17-3) The Smithsonian Astrophysical Observatory. A special site with lots of information about asteroids and comets.
How Asteroids are Named - (Web Link 17-3) This web page describes the designations that are given to minor planets. The Hubble Space Telescope has observed a huge crater on the surface of Vesta.
Map of Vesta's surface - (Web Link 17-4) The Hubble Space Telescope has also produced a map of Vesta's surface.
Asteroid's rotation - (Web Link 17-4) Hubble Space Telescope video of the asteroid's rotation.
Asteroid Radar Research - (Web Link 17-5) This web site describes how radar is used to map out
the surfaces of asteroids. It includes radar images of several minor planets. Mission home page. Spacecraft images of Gaspra and Ida can be found at this site.
The Nine Planets: 951 Gaspra - (Web Link 17-6) Each of the spacecraft that will explore a comet at close range has its own web site. Watch these sites for updates on the progress of each mission.
NEAR Shoemaker Encounters 253 Mathilde - (Web Link 17-6) This web site includes images, animations, and scientific results from the NEAR Shoemaker spacecraft's close
encounter with 253 Mathilde in 1997.
Near-Earth Asteroid Tracking (NEAT) - (Web Link 17-8) NEAT is an autonomous celestial observatory located at the USAF/Ground-based Electro-Optical Deep Space Surveillance (GEODSS) site on Haleakala, Maui, Hawaii. NEAT is a cooperative effort between NASA-JPL and the U.S. Air Force designed to complete a comprehensive search of the sky for near-Earth asteroids and comets.
Minor Planet Center NEO page - (Web Link 17-8) An extensive set of data concerning near-Earth
objects, along with links to other sites.
The Barringer Meteor Crater - (Web Link 17-9) A useful site about the impact crater in Arizona.
Terrestrial Impact Craters - (Web Link 17-9) A "slide show" from the Lunar and Planetary Institute describes an assortment of impact craters
on Earth and how they compare to craters found on other planets.
Views of the Solar System: Terrestrial Impact Craters - (Web Link 17-9)
The Nine Planets: Meteors, Meteorites, and Impacts - (Web Link 17-10)
Views of the Solar System: Meteoroids and Meteorites - (Web Link 17-10)
ANSMET: The Antarctic Search for Meteorites - (Web Link 17-10) One of the most productive places on Earth to search for meteorites is in Antarctica, where the ice traps
and preserves any objects falling from the sky. This search and some of its results are described at this site.
Meteorite Legends - (Web Link 17-10) An interesting collection of myths and beliefs about meteorites.
Comet Hale-Bopp - (Web Link 17-13) Complete information on the Great Comet of 1997, plus literally thousands of images of
this comet made by amateur and professional astronomers from around the world.
www.halebopp.com - (Web Link 17-13) An extensive web site about the Great Comet of 1997.
Debunks the curious notion that an object (some said it was a spaceship!) three to
four times the size of the Earth was following Comet Hale-Bopp. Scheduled for a 2002 launch, the CONTOUR spacecraft (Comet
Nucleus Tour) will fly past three comet nuclei and collect samples of cometary dust.
Deep Impact - (Web Link 17-14) This mission will send a large copper projectile crashing into the
surface of a comet, creating a huge crater and revealing the comet's internal
composition and structure.
Asteroid and Comet Impact Hazards - (Web Link 17-16) This NASA site describes the likelihood
of a major impact from space, and discusses the consequences of such an impact.
Impact Hazards: Truth and Consequences - (Web Link 17-16) Article by Gerrit Verschuur, Sky & Telescope, June 1998. Includes links to other sites with information about planetary impacts—especially impacts on Earth.
PART III Stars and Stellar Evolution
Chapter 18: Our Star, the Sun
Yohkoh Soft X-ray Telescope - (Web Link 18-1) The Soft X-ray Telescope (SXT) on board the
Yohkoh satellite has been observing the Sun since 1991. This web site has a diverse
collection of images from SXT.
The Nine Planets: The Sun - (Web Link 18-2) Information, images, and links to additional resources about the Sun.
Views of the Solar System: Sun - (Web Link 18-2) An educational tour of the solar system. The page on the Sun includes information, images,
animations, and links to more information.
Solar Physics on the Web - (Web Link 18-2) An exhaustive and comprehensive list of all sorts of
information about the Sun, including images.
Global Oscillation Network Group - (Web Link 18-3) One of the most active groups in helioseismology.
Solar Sounds - (Web Link 18-4) To create these sound files, Dr. Alexander Kosovichev of Stanford
University took data about the up-and-down oscillations of the Sun's surface and
speeded them up 42,000 times to bring them into the range of human hearing.
Solar Neutrino Experiments - (Web Link 18-5) This web site has links to information about the
Davis solar neutrino detector as well as other, more recent experiments.
GALLEX Experiment - (Web Link 18-6) This web site from the Max Planck Institute for Nuclear
Physics in Heidelberg, Germany has links to detailed information about GALLEX
and the discoveries it made about solar neutrinos. Images of the Chromosphere A number of observatories around the world study
the Sun's ever-changing chromosphere and make their images available on the
World Wide Web.
SOHO home page - (Web Link 18-9) Striking images and movies of the Sun are available at this site.
SOHO Extreme Ultraviolet Imaging Telescope - (Web Link 18-9) This site has an extensive collection of images and movies showing the appearance of the Sun at very short
ultraviolet wavelengths.
Ulysses/NASA home page - (Web Link 18-10) Data from the Ulysses spacecraft can be found at the mission's NASA web site.
Ulysses/ESA home page - (Web Link 18-10) Data from the Ulysses spacecraft can be found at the mission's ESA web site.
The Sunspot Cycle - (Web Link 18-11) This NASA web site describes sunspots and how their
number varies periodically, and includes the latest observations of sunspot activity.
The Magnetic Sun - (Web Link 18-12) This multimedia web site describes our current
understanding of how the Sun's rotation helps produce the solar magnetic field and
hence most of the activity we see on the Sun's surface. The TRACE Spacecraft A collection of web sites describe various aspects of
TRACE (Transition Region and Coronal Explorer) and its findings:
Solar Flare Theory - (Web Link 18-14) This web site from NASA's Goddard Space Flight Center
describes our current understanding of solar flares and what produces them.
Yohkoh Public Outreach Project - (Web Link 18-14) Yohkoh images, movies, classroom activities, and a solar tour can be found at this Montana State University site.
SpaceWeather.com - (Web Link 18-16)
This NASA site provides the latest information about the Sun-Earth environment.
Today's Space Weather - (Web Link 18-16)
This web site from the U.S. National Oceanic and Atmospheric Administration gives up-to-date information about solar radiation and geomagnetic storms.
International Solar-Terrestrial Physics - (Web Link 18-16)
Lots of solar news and resources.
Solar Data Analysis Center - (Web Link 18-16)
Images of the Sun and other solar information are made available on a daily basis at this site.
Chapter 19: The Nature of the Stars
The Sagittarius Star Cloud - (Web Link 19-1) Detailed information about the image that opens
Chapter 19, from the Hubble Space Telescope.
Delving into the personalities of stars - (Web Link 19-2) The stars visible with the naked eye and with a small telescope are not all the same but have a wide variety of physical attributes. This site at the University of Illinois gives insights into a different "Star of the Week" each week.
The Constellations and Their Stars - (Web Link 19-2) by Chris Dolan. Includes lists of constellations and stars, interactive sky charts, Milky Way photos, and answers to
frequently asked questions.
Stereoscopic Maps of Nearby Stars - (Web Link 19-3) The distribution of stars in space can best be visualized with 3-D images. A set of these showing the nearby stars can be found at this site.
The Hipparcos and Tycho Catalogues: Nearby Stars - (Web Link 19-3) Detailed information
about the stars nearest the Sun, using data from the Hipparcos satellite. The Hipparcos spacecraft was dedicated to the precise measurement of the positions, parallaxes, and
proper motions of the stars. Launched in August 1989, the satellite collected more than three years of
extremely high quality scientific data. Communications with the satellite were terminated in August 1993.
The web site includes a wealth of information about the spacecraft and its scientific bounty and even includes
3-D images of various constellations.
From Hipparchus to Hipparcos: Measuring the Universe, One Star at a
Time - (Web Link 19-4) This article by Catherine Turon, an astronomer at the Paris Observatory in
France, describes the history of how astronomers have measured the positions and
distances of to stars. Two Scientific American essays by Philip and Phyllis Morrison place the Hipparcos
measurements in historical context:
Hubble Space Telescope Astrometry Science Team - (Web Link 19-4) This site describes how a group of astronomers headquartered at the University of Texas uses the Hubble Space
Telescope to measure the positions and parallaxes of stars with great precision.
FAME, the Full-Sky Astrometric Mapping Explorer mission - (Web Link 19-4) Scheduled for launch in 2004, FAME is designed to determine with unprecedented accuracy the
positions, distances, and motions of 40 million stars within our galactic
neighborhood.
Barnard's Star - (Web Link 19-5) Information about the star whose position on the sky changes
most rapidly (that is, has the greatest proper motion).
Astronomy Picture of the Day: Gliese 710 - (Web Link 19-5) This fast-moving star will one day
come within 1 light-year of the Sun. These images from the Anglo-Australian Observatory reveal the
diverse colors of the stars.
Digital Images of the Sky - (Web Link 19-6) The color of a star or other astronomical object can tell us much more than the object's surface temperature,
as shown graphically this site at the University of Bonn.
The Stellar Magnitude System - (Web Link 19-7) This article from Sky & Telescope magazine
describes the historical origins of the magnitude scale as well as how it is used in
modern astronomy.
Stellar Spectra - (Web Link 19-8) A comprehensive discussion of the spectra of stars and what we
learn from them. The author, Professor James Kaler of the University of Illinois, is
an expert on stellar spectra. Spectral classes and how they came to be: The modern system of spectral
classes of stars comes from seminal work done in the late 19th and early 20th
centuries by a group of talented astronomers:
The Discovery of Brown Dwarfs - (Web Link 19-10) This Scientific American article by Professor
Gibor Basri of the University of California, Berkeley explains our present knowledge
of these "failed stars."
First Clear Evidence for Existence of a Brown Dwarf - (Web Link 19-10) Detailed information about the image in Figure 7-22, from the Hubble Space Telescope.
Observations of Young Brown Dwarfs - (Web Link 19-10) In 2000 the Very Large Telescope observed a brown dwarf companion of a young, nearby star.
A Vanishing Star - (Web Link 19-11) Detailed information about the eclipsing binary star depicted
in Figure 19-26e, from the European Southern Observatory.
Chapter 20: The Birth of Stars
A Star-Forming Region in Ara - (Web Link 20-1) Detailed information about the image that opens
Chapter 20, from the European Southern Observatory.
The Orion Nebula, M42 and M43 - (Web Link 20-2) Detailed information about the image in
Figure 20-1, from the Anglo-Australian Observatory.
SEDS Messier Database: M42 - (Web Link 20-2) Information about the Orion Nebula (M42 in the
Messier catalog of deep-sky objects).
The Horsehead Nebula, IC 434 and NGC 2024 in Orion - (Web Link 20-3) Detailed information about the image in Figure 20-2, from the Anglo-Australian Observatory.
The Web Nebulae - (Web Link 20-3) This site, created by Bill Arnett of Students for the Exploration and Development of Space (SEDS), includes an article on the types of nebulae, images of nebulae, and links to other sites about nebulae.
Images of Emission Nebulae from the Anglo-Australian Observatory. - (Web Link 20-3)
Dust cloud Barnard 86 and open cluster NGC 6520 - (Web Link 20-4) Detailed information
about the image in Figure 20-3, from the Anglo-Australian Observatory.
Images of Dark Nebulae from the Anglo-Australian Observatory. - (Web Link 20-4)
The Corona Australis nebula (NGC 6726-27-29) - (Web Link 20-5) Detailed information about
the image in Figure 20-4, from the Anglo-Australian Observatory.
Images of Reflection Nebulae from the Anglo-Australian Observatory. - (Web Link 20-5)
NGC 3576 and 3603 in Carina - (Web Link 20-6) Detailed information about the image in Figure
20-5, from the Anglo-Australian Observatory. Includes links to other, related
images.
Introduction to IRAS - (Web Link 20-7) This web page describes the hugely successful Infrared Astronomical Satellite (IRAS),
which observed the entire sky at wavelengths from 12 to 100 µm during the 1980s.
A spiral galaxy, NGC 5236 (Messier 83) - (Web Link 20-8) Detailed information about the image
in Figure 20-7a, from the Anglo-Australian Observatory.
SEDS Messier Database: M83 - (Web Link 20-8) Information about the galaxy M83 (part of the
Messier catalog of deep-sky objects).
The edge-on spiral galaxy NGC 891 - (Web Link 20-8) Detailed information about the image in
Figure 20-7b, from the Anglo-Australian Observatory.
SEDS Messier Database: NGC 891 - (Web Link 20-8) Information about the galaxy NGC 891.
Images of Galaxies from the Anglo-Australian Observatory. - (Web Link 20-8)
A group of Bok globules in IC 2948 - (Web Link 20-9) Detailed information about the image in
Figure 20-8, from the Anglo-Australian Observatory.
Astronomy Picture of the Day: Bok Globules - (Web Link 20-9)
Introduction to Infrared Astronomy - (Web Link 20-10) A tutorial from the Infrared Processing
and Analysis Center at the California Institute of Technology.
Seeing Our World in a Different Light - (Web Link 20-10) This web site from the SIRTF project
(Space Infrared Telescope Facility) describes the many applications of infrared light
in science, medicine, art, and industry.
The Two Micron All Sky Survey (2MASS) - (Web Link 20-10) This project, led by the University of
Massachusetts, is surveying the entire sky at near-infrared wavelengths. It will
detect objects 50,000 times fainter than those seen in previous surveys. The site
includes links to many 2MASS images of star-forming regions.
NICMOS Captures the Heart of OMC-1 - (Web Link 20-11) Detailed information about the image
in Figure 20-10, from the Hubble Space Telescope. This web page includes a link to
an animated ³zoom² into the Orion Nebula.
The Orion Nebula Project - (Web Link 20-11) An amazing 3-D animation of a "flight" through the
Orion Nebula, this is a joint project of the San Diego Supercomputer Center and the
American Museum of Natural History Hayden Planetarium.
Hubble Identifies What May Be the Most Luminous Star Known - (Web Link 20-12) Detailed information about the image in Figure 20-12, from the Hubble Space Telescope.
Peering into a Star Factory - (Web Link 20-12) The Very Large Telescope has made highly detailed
infrared images of young, massive stars in the Omega Nebula, a star-forming region
in the constellation Sagittarius.
HH1 and HH2: Star Jets - (Web Link 20-13) Detailed information about the image in Figure 20-13,
from Astronomy Picture of the Day.
Jets from a Young System of Three Stars - (Web Link 20-13) A combination of visible-light and infrared images gives a detailed look at a complex pair of jets ejected by a triple star
system.
Young Stellar Disks - (Web Link 20-14) The Hubble Space Telescope has been used to observe
accretion disks around a number of young stars.
Embryonic Stars and Evaporating Gaseous Globules - (Web Link 20-15) Images of the Eagle
Nebula from the Hubble Space Telescope reveal how evaporation helps to control the
sizes of stars as they form.
SEDS Messier Database: M16 - (Web Link 20-15) Information about the Eagle Nebula (M16 in the
Messier catalog of deep-sky objects).
SEDS Messier Database: Open Clusters - (Web Link 20-16) Information about open clusters, with
details about a number of open clusters that are easily seen with small telescopes.
Triggered Star Formation - (Web Link 20-17) Detailed information about the image in Figure 20-21, from the Hubble Space Telescope. The Cygnus Loop - (Web Link 20-18) Detailed information about the images in Figure 20-22 at Supernova remnants at X-ray wavelengths A number of orbiting x-ray observatories have produced stunning images of supernova remnants:
The Rosette Nebula and NGC 2244 - (Web Link 20-19) Detailed information about the image in
Figure 20-24, from the Anglo-Australian Observatory.
SEDS Messier Database: Rosette Nebula and NGC 2244 - (Web 20-19) Information about the Rosette Nebula and the adjoining open cluster.
Chapter 21: Stellar Evolution: After the Main Sequence
A mass-loss star in IC 2220 - (Web Link 21-1) Detailed information about the image that opens
Chapter 21, from the Anglo-Australian Observatory.
Main-sequence, post-main-sequence, and red giant stars - (Web Link 21-2) An informative web
page from the Electronic Universe project depicts how the internal structure of a star
evolves after it leaves the main sequence.
Life Cycle of the Stars - (Web Link 21-2) This web page from the University of Bradford has an
informative set of animations depicting the evolution of stars.
Open Cluster NGC 1857 - (Web Link 21-2) Detailed information about the image in Figure 21-3b,
from the Astronomical Institutes of the University of Bonn.
On the Planet of a Red Giant - (Web Link 21-3) An artist's rendition of what you might see from a
planet orbiting a red giant star.
H-R Diagrams from Hipparcos - (Web Link 21-4) This web page has several Hertzsprung-Russell
diagrams based on data compiled by the Hipparcos spacecraft.
SEDS Messier Database: Globular Clusters - (Web Link 21-5) Information about globular
clusters, with details about a number of globular clusters that are easily seen with
small telescopes.
Images of Globular Clusters from the Hubble Space Telescope - (Web Link 21-5)
Images of Globular Clusters from the Very Large Telescope - (Web Link 21-5)
Globular Cluster M10 - (Web Link 21-6) Detailed information about the image in Figure 21-8, from
the Astronomical Institutes of the University of Bonn.
SEDS Messier Database: M10 - (Web Link 21-6) Information about the globular cluster M10 (from
the Messier catalog of deep-sky objects).
SEDS Messier Database: M55 - (Web Link 21-7) Information about the globular cluster M55 (from the Messier catalog of deep-sky objects).
Mira (Omicron Ceti) - (Web Link 21-8) Information about the first pulsating variable star to be discovered.
Animations of variable stars - (Web Link 21-8) A web page at the University of Illinois has
animations made from observations of several variable stars, including Mira.
Types of variable stars, - (Web Link 21-8) from the American Association of Variable Star
Observers (AAVSO).
Delta Cephei - (Web Link 21-9) Information about the prototype Cepheid variable star.
The Discovery of the Period-Luminosity Relation for Cepehids - (Web Link 21-10) This web page reproduces Henrietta Leavitt's brief but seminal 1911 paper on the connection
between the period and luminosity of Cepheid variable stars.
Table of the Nuclides - (Web Link 21-12) This web site provides information about the relative
abundances of different types of nuclei. For example, it reveals that 3He makes up
only 0.000137% of the helium on Earth, while 4He makes up the other 99.999863%.
(Note that to this web site, the two types of helium are He3 and He4.)
The Top 12 Naked-Eye Variable Stars - (Web Link 21-13) A web page from Sky & Telescope magazine describes variable stars whose variations that can be seen even without a
telescope.
The American Association of Variable Star Observers - (Web Link 21-13) Web site explains how to observe variable stars.
SEDS Messier Database - (Web Link 21-13) Has information about many of the most prominent
star clusters.
Chapter 22: Stellar Evolution: The Deaths of Stars
The Glowing Eye of NGC 6751 - (Web Link 22-1) Detailed information about the image that opens
Chapter 22, from the Hubble Space Telescope.
SEDS Messier Database: M55 - (Web Link 22-2) Information about the globular cluster M55 (from
the Messier catalog of deep-sky objects).
TT Cygni: A Carbon Star - (Web Link 22-3) Detailed information about the image in Figure 22-4,
from Astronomy Picture of the Day.
Planetary Nebulae and the Future of the Solar System - (Web Link 22-4) An illustrated description of planetary nebulae from Professor Bruce Balick at the University of
Washington. Images of Planetary Nebulae from various sources:
A Dying Star in Globular Cluster M15 - (Web Link 22-4) Detailed information about the image in
Figure 22-6a, from the Hubble Space Telescope.
The Helix Nebula, NGC 7293 - (Web Link 22-4) Detailed information about the image in Figure 22-6b, from the Anglo-Australian Observatory.
Hubble Captures the Shrouds of Dying Stars - (Web Link 22-4) Detailed information about the image in Figure 22-6c, from the Hubble Space Telescope.
The Hourglass Nebula - (Web Link 22-5) Detailed information about the image in Figure 22-7, from the Hubble Space Telescope. Subrahmanyan Chandrasekhar, a pioneer in understanding white dwarf stars,
was one of the foremost astrophysicists of the twentieth century. Here is information
about his life and discoveries.
A Wolf-Rayet Star in NGC 2359 - (Web Link 22-7) Detailed information about the image in Figure
22-12, from the Anglo-Australian Observatory.
A Wolf-Rayet Star Blows Bubbles - (Web Link 22-7) Astronomy Picture of the Day
The Large Magellanic Cloud - (Web Link 22-8) Information about the dwarf galaxy that is home to Supernova 1987A.
Images of Supernova 1987A - (Web Link 22-9) from the Anglo-Australian Observatory. The Rings of Supernova 1987A The explosion of SN 1987A has affected the
material that the progenitor star earlier ejected into space, causing that material to
appear as glowing rings. Here are links to information about the rings from various
sources:
An Introduction to Neutrino Astronomy - (Web Link 22-11) by Professor John Learned of the
University of Hawaii. Information about this pioneering Japanese neutrino observatory.
The Irvine-Michigan-Brookhaven Experiment (IMB) - (Web Link 22-11) Like Kamiokande, IMB detected neutrinos emitted by Supernova 1987A.
SEDS Messier Database: M81 - (Web Link 22-12) Information about the spiral galaxy M81 (from
the Messier catalog of deep-sky objects).
Radio Images of Supernova 1993J - (Web Link 22-12) Using the Very Long Baseline Array,
astronomers were able to make a "movie" of the expansion of debris from Supernova
1993J.
An Introduction to Supernova Remnants - (Web Link 22-13) from NASA's High Energy
Astrophysics Science Archive Research Center, with special emphasis on observing
these remnants at X-ray wavelengths.
Images of Supernova Remnants - (Web Link 22-13) from the Anglo-Australian Observatory.
Chandra Maps Vital Elements in Supernova - (Web Link 22-14) Detailed information about the
image in Figure 22-14a, from the Chandra X-ray Observatory.
Cassiopeia A at Many Wavelengths - (Web Link 22-14) By observing a supernova remnant at radio,
infrared, visible, and x-ray wavelengths, astronomers learn about complementary
aspects of the remnant.
X-ray Star Stuff - (Web Link 22-14) The Chandra X-ray Observatory has observed the characteristic
emissions of silicon, calcium, and iron in the Cassiopeia A supernova remnant.
These observations give insight into how supernovae seed the interstellar medium
with heavy elements.
Chapter 23: Neutron Stars
The Crab Nebula at Many Wavelengths - (Web Link 23-1) By observing the Crab Nebula at radio,
infrared, visible, and x-ray wavelengths, astronomers learn about complementary
aspects of this supernova remnant.
Supernova 1054 - Creation of the Crab Nebula - (Web Link 23-2) This web page, from the Students for the Exploration and Development of Space, describes
contemporary observations of the 1054 supernova by observers in North America, Asia, and
perhaps Europe.
Jocelyn Bell Burnell - (Web Link 23-3) Information about the discoverer of the first four pulsars,
from the "Contributions of 20th Century Women to Physics" web site at UCLA. The Sounds of Pulsars Just as an ordinary radio converts radio broadcasts into speech or music, astronomers have
converted radio signals from pulsars into audio recordings. These are samples of "pulsar sounds"
from
Pulsar Research - (Web Link 23-5) Nuffield Radio Astronomy Laboratories, University of Manchester. Includes an introduction to pulsar astronomy, current research projects, and resources (including links to related web sites).
Pulsar Images and Information - (Web Link 23-5) from NASA's High Energy Astrophysics Science Archive Research Center.
Pulsar B1757-24 - (Web Link 23-6) Detailed information about the image in Figure 23-6, from the
National Radio Astronomy Observatory.
Hubble Sees Bare Neutron Star Streaking Across Space - (Web Link 23-6) Astronomers using the Hubble Space Telescope have observed an isolated neutron star moving through
space at hundreds of thousands of kilometers per hour.
SEDS Messier Database: M1 - (Web Link 23-7) Information about the Crab Nebula (M1 in the Messier catalog of deep-sky objects).
Science Background: A History of the Crab Nebula - (Web Link 23-7) from the Space Telescope Science Institute.
An Introduction to Synchrotron Radiation - (Web Link 23-8) from the Australian Nuclear Science and Technology Organisation.
The Rossi X-Ray Timing Explorer Project - (Web Link 23-9) Massachusetts Institute of Technology. An especially good site with data from this project.
The Rossi X-ray Timing Explorer Learning Center - (Web Link 23-9) An extensive multimedia web site describing the satellite and the discoveries it has
made about neutron stars and other exotic objects.
A Millisecond Pulsar - (Web Link 23-9) Information about the X-ray-emitting millisecond pulsar
SAX J1808.4-3658. An animation shows how mass transfer from the companion
star has made the neutron star spin up.
X-ray Source-Neutron Stars - (Web Link 23-10) An introduction to X-ray-emitting neutron stars,
with an animation and links to images from the Chandra X-ray Observatory.
A "2-in-1" X-ray Burster - (Web Link 23-10) A description of an unusual X-ray burster that emits
bursts twice per orbit as it passes through its companion star's accretion disk. New astronomical phenomena such as novae are often reported on the web sites
The IAU Central Bureau for Astronomical Telegrams - (Web Link 23-11) has up-to-date information on transient astronomical phenomena such as novae. Discoveries of new
comets, asteroids, and satellites of the planets are also reported here.
Chapter 24: Black Holes
Accretion Disks in Binary Systems - (Web Link 24-1) This web page from Astronomy Picture of
the Day has links to information about accretion disks in a variety of close binary
star systems, including those in which one of the stars is a black hole.
The Light Cone - (Web Link 24-2) is an illuminating introduction to relativity theory by Rob
Salgado at Syracuse University.
Relativity on the World Wide Web - (Web Link 24-2) An extensive collection of links to educational sites.
Gravitational Waves from a Binary Pulsar - (Web Link 24-4)
A description of how the change in orbital period of a binary pulsar gives evidence for the existence of gravitational waves. The co-discoverers of this phenomenon, Russell Hulse and Joseph Taylor, shared the 1993 Nobel Prize in Physics.
LIGO (Laser Interferometer Gravitational-Wave Observatory) - (Web Link 24-4)
A facility dedicated to the detection of cosmic gravitational waves and the harnessing of these waves for scientific research.
The Virgo Project - (Web Link 24-4)
A collaboration between Italian and French research teams, to create an interferometric gravitational wave detector.
Laser Interferometer Space Antenna (LISA) - (Web Link 24-4)
Mission to detect and observe gravitational waves from massive black holes and galactic binary stars.
Gravitational Wave Experiments - (Web Link 24-4)
A master list of web sites for current and planned experiments designed to detect gravitational radiation.
Black holes in X-ray emitting binaries - (Web Link 24-5)
A "field guide" to black holes whose accretion disks emit X rays, with link to Chandra X-ray Observatory images of these objects.
SEDS Messier Database: M87 - (Web Link 24-6)
Information about the galaxy M87 (one of the Messier catalog of deep-sky objects).
Supermassive Black Holes
Astronomers have observed supermassive black holes in a number of galaxies. These include
Chandra Observes a "Missing Link" Black Hole - (Web Link 24-7)
Astronomers using the orbiting Chandra X-ray Observatory have confirmed the presence of an black hole with a mass of more than 500 Suns. This is intermediate between the stellar-mass black holes found in binary star systems and the supermassive black holes found at the centers of galaxies. This "missing link" between small and large black holes lies in the galaxy M82.
M82's Middle Mass Black Hole, - (Web Link 24-7) from Astronomy Picture of the Day.
SEDS Messier Database: M82 - (Web Link 24-7)
Information about the galaxy M82 (one of the Messier catalog of deep-sky objects).
Earth Dragging Space and Time as it Rotates - (Web Link 24-8)
Satellite measurements indicate that the Earth is dragging space and time around itself as it rotates‹in agreement with a prediction of the general theory of relativity.
The LAGEOS Program - (Web Link 24-8)
Information about the spacecraft used to detect the "dragging" of spacetime.
Falling into a Black Hole - (Web Link 24-9)
Created by Andrew Hamilton at the University of Colorado, takes an in-depth look at what happens when you fall into a black hole.
Virtual Trips to Black Holes and Neutron Stars - (Web Link 24-9)
Take a virtual trip to black holes and neutron stars at this site maintained by Robert Nemiroff of Michigan Technical University and NASA-Goddard.
The Particle Adventure - (Web Link 24-10)
A multimedia introduction to subatomic particles, their interactions, and the experiments that physicists carry out to study them.
The Science of Particle Physics - (Web Link 24-10) is the study of the fundamental nature of matter. This web site from the Fermi National Accelerator Laboratory gives insight into all aspects of this exciting subject.
PART IV Galaxies and Cosmology
Chapter 25: Our Galaxy
SEDS Messier Database: Globular Clusters - (Web Link 25-2) Information about globular
clusters, with details about a number of globular clusters that are easily seen with
small telescopes.
Images of Globular Clusters from the Hubble Space Telescope - (Web Link 25-2)
Images of Globular Clusters from the Very Large Telescope - (Web Link 25-2)
SEDS Messier Database: M55 - (Web Link 25-3) Information about the globular cluster M55 (from
the Messier catalog of deep-sky objects).
M55 in Color - (Web Link 25-3) from Astronomy Picture of the Day.
Introduction to Infrared Astronomy - (Web Link 25-4) A tutorial from the Infrared Processing and
Analysis Center at the California Institute of Technology. One page in this site
describes the difference between near-, mid-, and far-infrared wavelengths, and what
we learn from observations in these different wavelength regions.
Multiwavelength Milky Way - (Web Link 25-5) Maps of the Milky Way in eight wavelength bands–infrared, near-infrared, visible, X-ray, gamma-ray, radio emissions from hydrogen atoms and from free electrons, and the microwave emissions from carbon monoxide molecules–are available at this NASA Astrophysics Data Facility site.
Cosmic Background Explorer (COBE) - (Web Link 25-5) Launched in 1989, COBE had as its
primary goal the investigation of radiation left over from the very early universe. In
addition, COBE returned a harvest of information about the Milky Way Galaxy. Information about the galaxy NGC 4565, from Astronomy Picture of
the Day.
The Basics of MRI - (Web Link 25-7) This web site at the Rochester Institute of Technology gives an in-depth introduction to magnetic resonance imaging.
SEDS Messier Database: M83 - (Web Link 25-8) Information about the galaxy M83 (from the
Messier catalog of deep-sky objects).
2MASS Atlas Image Galleries: Galaxies - (Web Link 25-8) This site from the Two Micron All Sky
Survey has near-infrared images of a variety of galaxies, including M82.
Dark Matter in the Universe - (Web Link 25-9) An overview of the evidence for dark matter in our
Galaxy and other galaxies. The author, Dr. Vera Rubin, has done pioneering research
into the structure of the Milky Way, motions within galaxies, and large-scale
motions in the universe. A clearly-written introduction to the subject, from the Center for
Particle Astrophysics at Berkeley. Includes links to other dark matter information
on the Web.
Dark Matter Mystery - (Web Link 25-9 These web pages at the Harvard-Smithsonian Center for
Astrophysics review the various proposals for what dark matter could be.
Dark Matter Links - (Web Link 25-9) from Astronomy Picture of the Day.
The Macho Project - (Web Link 25-10) This site describes the search for MACHOs and includes links to data, publications, images, and other web sites related to the search for dark matter.
WIMPs (UK Dark Matter Collaboration site) - (Web Link 25-11)
Beyond the Blue: Greatest Hits of the Ultraviolet Imaging Telescope - (Web Link 25-12) Hot O and B stars in spiral arms emit copious amounts of ultraviolet light. The ultraviolet
images of galaxies at this web site provide a unique perspective on spiral structure.
Multiwavelength Messier Museum - (Web Link 25-12) This web site has images at many
wavelengths of a variety of objects from the Messier catalog, including galaxies. The latest research news about the galactic center can be found in the online newsletter.
The Black Hole in the Galactic Center - (Web Link 25-14) This online slide show, created by
astronomers Heino Falcke, Fulvio Melia, and Eric Agol, will lead you into the very
heart of the Galaxy. A key topic is a proposal to observe the event horizon of the
supermassive black hole at the Galaxy's center.
Chapter 26: Galaxies
SEDS Messier Database: M31 - (Web Link 26-1) Information about the Andromeda Galaxy, M31
(from the Messier catalog of deep-sky objects).
Chandra Finds "Cool" Black Hole at the Heart of Andromeda - (Web Link 26-1) The Chandra
X-ray Observatory has detected emissions from a supermassive black hole at the
center of M31.
SEDS Messier Database: M32 - (Web Link 26-1) Information about the brighter of the two small
elliptical galaxies that orbit M31 (from the Messier catalog of deep-sky objects).
SEDS Messier Database: M110 - (Web Link 26-1) Information about the dimmer of the two small
elliptical galaxies that orbit M31 (from the Messier catalog of deep-sky objects).
SEDS Messier Database: M51 - (Web Link 26-2) Information about the Whirlpool Galaxy, M51
(from the Messier catalog of deep-sky objects).
The Shapley-Curtis Debate of 1920 - (Web Link 26-3) This web page describes the "Great Debate"
over the theory that spiral nebulae are actually galaxies like our own.
Cepheid Variables in M100 - (Web Link 26-4) Images, animations, and text describe how
astronomers use the Hubble Space Telescope to observe Cepheid variable stars in
other galaxies and thus determine the distances to those galaxies.
The Galaxy Catalog at Princeton University - (Web Link 26-5) From Princeton University a collection of digital images of 113 nearby galaxies.
Galaxies (Anglo-Australian Observatory) - (Web Link 26-5)
Several beautiful images of galaxies are available from the Anglo-Australian Observatory.
NSSDC Photo Gallery: Galaxies and Globular Clusters - (Web Link 26-5) A collection of images of galaxies, plus one globular cluster.
SEDS Messier Database - (Web Link 26-5)
A number of the more prominent galaxies are part of the Messier Catalog of bright deep-sky objects. Images and descriptions of these galaxies can be found at this site maintained by Students for the Exploration and Development of Space (SEDS).
Images of Galaxies from the Very Large Telescope. - (Web Link 26-5)
SEDS Messier Database: M84 - (Web Link 26-6) Information about the giant elliptical galaxy M84
(from the Messier catalog of deep-sky objects). A number of the more prominent galaxies are part of the Messier Catalog of bright deep-sky objects. Images and descriptions of these galaxies can be found at this site maintained by Students for the Exploration and Development of Space (SEDS).
SEDS Messier Database: M86 - (Web Link 26-6) Information about the giant elliptical galaxy M86
(from the Messier catalog of deep-sky objects).
LMC Images and Links - (Web Link 26-7) from Astronomy Picture of the Day
NGC 1850: Star Cluster in the LMC - (Web Link 26-7) from Astronomy Picture of the Day
The LMC in X-rays - (Web Link 26-7) from XMM-Newton (European Space Agency)
SMC Images and Links - (Web Link 26-8) from Astronomy Picture of the Day
N81: Star Cradle in the SMC - (Web Link 26-8) from Astronomy Picture of the Day
The ABC's of Distances - (Web Link 26-9) A description of 26 different techniques that
astronomers use to measure distances beyond the solar system.
Supernovae in Other Galaxies - (Web Link 26-11) More information about the supernova shown in Figure 26-13.
Radio Astronomers Set New Standard for Accurate Cosmic Distance
Measurement - (Web Link 26-12) Using the Very Long Baseline Array, astronomers have determined
the distance to a galaxy by observing the motions of masers - clouds that are
powerful sources of microwaves - as they orbit the galaxy's center.
A Biography of Edwin Hubble - (Web Link 26-13) This article by astronomer Allen Sandage
describes how Hubble discovered the expansion of the universe, as well as Hubble's
many other contributions to astronomy.
Cosmology Tutorial - (Web Link 26-13) Professor Ned Wright at UC-Los Angeles maintains this
excellent site, which tells more of the history of Hubble's discovery of the law that
bears his name.
European Southern Observatory's Very Large Telescope - (Web Link 26-14)
The Sagittarius Dwarf - (Web Link 26-15) This web page from Astronomy Picture of the Day
describes evidence that the Sagittarius Dwarf galaxy is on a collision course with the
Milky Way - and that it has collided with our Galaxy in the past.
The Local Group of Galaxies - (Web Link 26-15) Up-to-date information about the Local Group is available at this SEDS site.
The Hercules Cluster - (Web Link 26-16) More information about the cluster of galaxies shown in
Figure 26-21, from Astronomy Picture of the Day. Redshift Surveys Several research groups are observing extremely distant
galaxies in an effort to create three-dimensional maps of their distribution in space.
These new maps may allow us to understand the origin of structures such as voids
and sheets of galaxies.
Chandra Maps Abell 2142 - (Web Link 26-18) Detailed information about the X-ray image of a
cluster of galaxies in Figure 26-23.
Other Chandra X-ray Images of Clusters of Galaxies - (Web Link 26-18) can be found at a web
page that presents all public Chandra images sorted by category.
XMM-Newton Mosaics the Coma Cluster of Galaxies - (Web Link 26-18) In addition to having a wide selection of galaxies, the Coma cluster (Figure 26-17) contains tremendous
amounts of X-ray emitting gas. Images from the XMM-Newton orbiting X-ray
Observatory reveal the structure of this gas.
SEDS Messier Database: M82 - (Web Link 26-19) Information about the galaxy M82 (one of the
Messier catalog of deep-sky objects).
Galaxy Transformations - (Web Link 26-20)
A number of still images and video clips of simulated galaxy collisions are available at this web site maintained by Joshua Barnes at the University of Hawaii Institute for Astronomy.
Hubble Reveals Stellar Fireworks Accompanying Galaxy Collisions - (Web Link 26-21) Detailed information about the image in Figure 26-27, from the Hubble Space
Telescope.
The Metamorphosis of the Local Group - (Web Link 26-22)
This site, created by John Dubinski at the University of Toronto, has a series of photographs showing what might happen when the Milky Way and Andromeda galaxies collide—an event that is expected to occur in several billion years—as well as a movie simulating the collision.
Gravitational Lens Captures Image of Primeval Galaxy - (Web Link 26-23) Detailed information about the image in Figure 26-31, from the Hubble Space Telescope.
Gravitationally Lensed Galaxies - (Web Link 26-23) This web page has several excellent images of
gravitational lenses made by the Very Large Telescope.
Hubble Sees Early Building Blocks Of Today's Galaxies - (Web Link 26-24) Detailed information about the images shown in Figure 26-34.
Cosmic Collisions - Merging Galaxies Caught in the Act - (Web Link 26-24) Hubble Space Telescope images of more than a dozen very distant colliding galaxies indicate that,
at least in some cases, big massive galaxies form through collisions between smaller
ones.
Hubble Space Telescope: Distant Galaxies - (Web Link 26-25) A collection of images with detailed information on their scientific background.
Chapter 27: Quasars, Active Galaxies, and Gamma-Ray Bursters
Chandra Observes Cosmic Traffic Pile-Up In Energetic Quasar Jet - (Web Link 27-1) An image from the Chandra X-ray Observatory shows fine detail in a jet of high-speed
particles emanating from the quasar 3C 273. This site also has links to images of
the quasar at other wavelengths.
The Brightest Quasar: 3C 273 and its Jet - (Web Link 27-1) This web page shows the structure of 3C 273 at visible and infrared wavelengths.
Early Radio Astronomy: The Ham Radio Connection - (Web Link 27-2) This web page from the national Radio Astronomy Observatory describes how radio
astronomy evolved as a direct descendent of amateur radio.
The Web Window to the Invisible Universe - (Web Link 27-2) An interactive map of the sky at radio wavelengths is a great help in visualizing
the distribution of quasars.
Active Galaxies and Quasars - (Web Link 27-3) Bill Keel at the University of Alabama created this web version of a slide set covering QSOs and
other kinds of active galaxies produced by the Astronomical Society of the Pacific. Includes examples
of Seyfert galaxies, radio galaxies, and quasars.
Hubble Space Telescope: Quasars and Active Galaxies - (Web Link 27-3) An extensive collection of telescope images and artist's conceptions.
Astronomy Picture of the Day: Quasars - (Web Link 27-3) A collection of links to images and descriptions of quasars.
Halton C. Arp and the Peculiar Galaxies - (Web Link 27-4) This web page from the Astronomical League explores the controversy about the nature of quasars.
Atlas of Peculiar Galaxies - (Web Link 27-4) Halton Arp used the images in this atlas to argue
that quasars are not as distant as their redshifts might suggest.
Hubble Surveys The "Homes" Of Quasars - (Web Link 27-5) Further information about the images in Figure 27-9, from the Hubble Space Telescope.
Seyfert Galaxies - (Web Link 27-6) An overview of these active spiral galaxies, from the Students for the Exploration and Development of Space (SEDS). Images of Seyfert Galaxies Because Seyfert galaxies are spirals, they are among the most aesthetically pleasing of
active galaxies. Here are links to more information about several Seyferts:
The Circinus Galaxy - (Web Link 27-6) (from the Hubble Space Telescope)
NGC 1068 (M77) - (Web Link 27-6) (from SEDS)
NGC 1566 - (Web Link 27-6) (from the Anglo-Australian Observatory)
NGC 4945 - (Web Link 27-6) (from the European Southern Obervatory)
NGC 7742 - (Web Link 27-6) Further information about the image in Figure 27-10, from the Hubble Space Telescope. More information about the Seyfert galaxy depicted in Figure 27-11.
SEDS Messier Database: M87 - (Web Link 27-8) Information about one of the most dramatic of all radio galaxies.
A Cosmic Searchlight - (Web Link 27-8) More information about M87's jet shown in Figure 27-12, from the Hubble Space Telescope.
M87 at Various Wavelengths - (Web Link 27-8) from the Multiwavelength Messier Museum at Caltech. Spectacular Structure in M87 - (Web Link 27-8) For several years, astronomers studying the active galaxy M87 have known about the energetic jet of material
being ejected from what is presumably a supermassive black hole at the center of the galaxy. A recent wide-angle
radio image of M87 shows that the center of the galaxy is also surrounded by two enormous radio-emitting
regions spanning some 60 kiloparsecs (200,000 light-years). These regions may be "bubbles" of hot
gas heated by material flowing outward from the galaxy's core.
NGC 5128 (Centaurus A) - (Web Link 27-9) Information from the Students for the Exploration and Development of Space (SEDS). This web site from the Chandra X-ray Observatory Center has
images of Centaurus A at several different wavelengths, including a high-resolution
image of the X-ray jet.
Starbirth in Centaurus A - (Web Link 27-9) A detailed image from the Hubble Space Telescope reveals new star formation in NGC 5128,
presumably triggered by the collision between two galaxies.
Superluminal Motion in the M87 - (Web Link 27-10) Jet Astronomers have used the Hubble Space Telescope to make the first visible-light
observations of superluminal motion in a radio galaxy's jet. Chandra Spies a Black Hole in M31 The Chandra X-ray Observatory has observed radiation from high-temperature gases
spiraling into a supermassive black hole at the center of the Andromeda Galaxy.
VLBA Reveals Formation Region of Giant Cosmic Jet Near a Black Hole - (Web Link 27-12) A team of astronomers have used radio telescopes, including the Very Long Baseline
Array, to view the inner region of the active galaxy M87. Their observations reveal
the region where particles escaping from the central accretion disk are focused into a
long, straight jet. Black Holes in Active Galaxies The Hubble Space Telescope has made observations indicating the presence of accretion disks
around supermassive black holes in a number of galaxies.
Nearby Quasars Result From Galactic Encounters - (Web Link 27-14) New radio images of three nearby quasars (within a few hundred megaparsecs) reveal that these quasars lie within
galaxies that have recently interacted with other, adjoining galaxies. These observations reinforce the idea that
nearby quasars occur in mature galaxies in which a central black hole is "fed" new material from another
galaxy during a galactic interaction. By contrast, distant quasars (which are thousands of megaparsecs away) seem
to lie within young galaxies. Such galaxies have enough interstellar gas and dust to "feed" their central
black hole and produce a quasar.
High Energy Astrophysics Science Archive Research Center - (Web Link 27-15) The search for high-energy radiation from gamma-ray bursters and other cosmic exotica is the subject of
this NASA Goddard Space Flight Center web site.
Gamma-Ray Bursts - (Web Link 27-15) A collection of web pages about gamma-ray bursts, from Astronomy Picture of the Day.
Gamma-Ray Burster Sky Maps - (Web Link 27-16) More information about maps of gamma-ray bursts such as Figure 27-26, from
Astronomy Picture of the Day.
The Fading Light of a Gamma-Ray Burster - (Web Link 27-17) Telescopes on the ground and in space have helped confirm that a gamma-ray burster
observed in December 1997 took place within a very distant galaxy.
Robotic telescope captures visible light from a powerful gamma-ray burst - (Web Link 27-17) The visible-light images in Figures 27-27 and 27-28 were made several days after a
gamma-ray burster was spotted. This web page describes the first simultaneous
observations of visible light and gamma rays from a gamma-ray burster.
The Host Galaxy of a Gamma-Ray Burster - (Web Link 27-18) The Hubble Space Telescope has revealed details about the host galaxy of an
unusually bright gamma-ray burster.
A Ringside Seat for a Gamma-Ray Burst - (Web Link 27-19) This article describes one model of how a supernova could give rise to a gamma-ray
burster by producing intense beamed radiation.
Coalescing Neutron Stars and Gamma Ray Bursters - (Web Link 27-19) Maximilian Ruffert of the Max Planck Institute for Astrophysics has created supercomputer
simulation "movies" of colliding neutron stars—a leading model for gamma-ray bursters.
Are Gamma-Ray Bursters Super-Supernovae? - (Web Link 27-19) An unusually bright supernova in a distant spiral galaxy appeared in the same part of the sky, and at
the same time, as a recent gamma-ray burster (GRB). Was this merely a remarkable coincidence, or could
GRBs be caused by such unusual supernovae?
What Gamma-Ray Bursters Are Not - (Web Link 27-19) One leading model that attempted to explain the origin of the mysterious gamma-ray bursters was
the "synchrotron shock." In this model, a tremendous explosion generates a shock wave that
accelerates charged particles, such as electrons and protons, to velocities near the speed of light.
But recent observations have shown that this model cannot explain the spectrum of radiation emitted by
gamma-ray bursters. The true nature of these celestial cataclysms remains a mystery. Information about the new generation of orbiting gamma-ray telescopes:
Backyard Gamma-Ray Bursts - (Web Link 27-20) The HETE-2 satellite will make it possible for amateur astronomers to participate in gamma-ray burster research.
Chapter 28: Cosmology: The Creation and Fate of the Universe
Hubble Pinpoints Distant Supernovae - (Web Link 28-1) Information about the supernova shown
in the image that opens Chapter 28. By analyzing the light from such distant
supernovae, astronomers have found that the expansion of the universe is speeding
up.
Professor Ned Wright at UC-Los Angeles maintains this excellent online cosmology tutorial, complete with frequently asked questions, common fallacies in cosmology, and information on the most recent research in cosmology.
Introduction to Cosmology - (Web Link 28-2)
NASA's Goddard Space Flight Center provides its own cosmology tutorial, as well as a wealth of information (including images) from the COBE spacecraft.
Albert Einstein - (Web Link 28-3)
Biographical information about Einstein and his work, as well as links to many other Einstein-related web sites.
A Biography of Edwin Hubble - (Web Link 28-4)
This article by astronomer Allen Sandage describes how Hubble discovered the expansion of the universe, as well as Hubble's many other contributions to astronomy.
Cosmology Tutorial: The Hubble Law - (Web Link 28-4)
The history of Hubble's discovery of the law that bears his name.
220 Frequently-Asked Questions about Cosmology - (Web Link 28-5)
Dr. Sten Odenwald, an astronomer and science writer, answers the most common questions about the sometimes vexing notion of an expanding universe.
Frequently Asked Questions in Cosmology - (Web Link 28-6) - along with their answers - from Professor Ned Wright at UCLA.
The Age of the Universe - (Web Link 28-6)
This page from Prof. Ned Wright's web site describes observational limits on the age of the universe.
Dating the Universe with Uranium - (Web Link 28-6)
Using the European Southern Observatory's Very Large Telescope, astronomers have detected a spectral line of uranium in one of the oldest stars in the Milky Way Galaxy. The abundance of uranium in this star implies that the universe is at least 12.5 billion years old.
The Cosmic Background Explorer (COBE) - (Web Link 28-8)
The web site for COBE - the first spacecraft to map the cosmic background radiation with high precision - includes a wealth of images, movies, and maps of the sky at different wavelengths.
Galaxies Behind the Milky Way - (Web Link 28-9)
The "Great Attractor" is hidden from direct view by obscuring dust in the plane of the Milky Way. This article by astronomers Renée C. Kraan-Korteweg and Ofer Lahav describes recent advances that have made it possible to see through this obscuration.
Galaxies Cluster Toward the Great Attractor - (Web Link 28-9)
Observations from the European Southern Observatory reveal galaxies that may be part of the immense grouping of galaxies known as the "Great Attractor."
VLT Observations Confirm that the Universe Was Hotter in the Past - (Web Link 28-10)
By analyzing the spectrum of an extremely distant quasar, an international team of astronomers have determined the radiation temperature of the universe as it was some 12 billion years ago. Their result - between 6 and 12 K - is indeed higher than the present-day value of 2.725 K, as predicted by Big Bang cosmology.
MAXIMA Finds Evidence for a Flat Universe - (Web Link 28-12)
This article from the University of California, Berkeley, summarizes the results from MAXIMA and BOOMERANG, and explains how they imply the existence of "dark energy" - perhaps in the form of a cosmological constant.
Dark Energy and the Microwave Background - (Web Link 28-12)
By analyzing recent data from precision measurements of the cosmic microwave background, physicists have concluded that the density parameter is very close to 1 - thus implying the presence of substantial amounts of dark energy.
Evidence for an Accelerating Universe - Working independently, two research groups have used observations of Type Ia supernovae to conclude that the expansion of the universe is speeding up.
News of the Accelerating Universe - (Web Link 28-13)
A collection of links to articles about the evidence for an accelerating universe.
Making Sense of Modern Cosmology - (Web Link 28-14)
This Scientific American article by Professor P. J. E. Peebles of Princeton University gives a "report card" on the latest ideas in cosmology.
Cosmology from Space The following links provide information about a new generation of space missions designed to measure the key parameters of cosmology.
Microwave Anisotropy Probe (MAP) - (Web Link 28-14)
A NASA mission to measure temperature variations in the cosmic microwave background with better precision than ever before. Its goal is to answer three questions: What are the values of the cosmological parameters of the Big Bang theory? How did structures of galaxies form in the universe? And when did the first structures of galaxies form?
A European Space Agency mission which will complement MAP by studying the cosmic background radiation with extremely high precision.
Supernova/Acceleration Probe (SNAP) - (Web Link 28-14)
This proposed mission will measure several thousand distant supernovae, thus providing more accurate data about the expansion history of the universe.
Chapter 29: Exploring the Early Universe
The Relativistic Heavy Ion Collider - (Web Link 29-1) at the Brookhaven National Laboratory is
able to probe the inner workings of matter. By colliding massive nuclei with each
other at speeds approaching the speed of light, RHIC creates extreme conditions like
those that existed in the Big Bang. The image that opens Chapter 29 shows the
result of such a collision.
Inflation for Beginners - (Web Link 29-2) An introduction to the inflationary model, by science
writer John Gribbin.
The Particle Adventure - (Web Link 29-3) A tour of the inner workings of the atom from the University of California's Lawrence
Berkeley Laboratory. Includes a wonderful chart of fundamental particles and interactions.
A Brief Overview of High-Energy Physics - (Web Link 29-3) From the Fermi National Accelerator Laboratory.
Werner Heisenberg and the Uncertainty Principle - (Web Link 29-4) An exhibit covering
Heisenberg's physics, career, personal, and political life, from the Center for History
of Physics of the American Institute of Physics.
Cosmology Tutorial: The Hubble Law - (Web Link 29-4) The history of Hubble's discovery of the law that bears his name.
The Formation of the Elements - (Web Link 29-5) A web page from the Lawrence Berkeley
National Laboratory explains the steps involved in the formation of light elements
in the Big Bang.
Big-Bang Nucleosynthesis: Linking Inner Space and Outer Space - (Web Link 29-5) This web
site provides additional details about the origin of the chemical elements, as well as
how the abundances of the elements help us to understand aspects of elementary
particle physics.
SEDS Messier Database: Globular Clusters - (Web Link 29-7) Information about globular
clusters, with details about a number of globular clusters that are easily seen with
small telescopes.
Images of Globular Clusters - (Web Link 29-7) from the Hubble Space Telescope
Images of Globular Clusters - (Web Link 29-7) from the Very Large Telescope
Cosmos in a Computer - (Web Link 29-8)
From the National Center for Supercomputing Applications
Some Movies of the Galaxy Formation Group - (Web Link 29-8)
The Max Planck Institute for Astrophysics in Germany
N-Body Simulation Images and Animations - (Web Link 29-8)
from the Theoretical Astrophysics group at Los Alamos National Laboratory
Big Bang Science - (Web Link 29-9) A web site from the Rutherford Appleton Laboratory describes
theoretical and experimental progress in the quest to understand the unification of
the four physical forces.
The 1979 Nobel Prize in Physics - (Web Link 29-10) was shared by Sheldon Glashow, Abdus
Salam, and Steven Weinberg for their unification of the electromagnetic and weak
forces. This web page from the Nobel Foundation describes their work.
The Official String Theory Web Site - (Web Link 29-11) An extensive web site describes efforts to
develop a fundamental theory of all elementary particles and the forces they exert on
each other.
Chapter 30: The Search for Extraterrestrial Life
Cold Methane Environments on the Ocean Floor - (Web Link 30-1) This web page reviews many
of the curious life forms that have been discovered in the cold depths of the ocean.
Images of Methane Iceworms - (Web Link 30-1) from Professor Charles Fisher at Pennsylvania
State University.
Astrobiology at NASA - (Web Link 30-2) The National Aeronautics and Space Administration is
supporting a major research effort in the field of astrobiology. This web site has
links to many of their ongoing projects.
The NASA Astrobiology Institute - (Web Link 30-2) is a partnership between NASA and other
research institutions. Their site has an extensive collection of background
information.
The Origins Program - (Web Link 30-2) is one of NASA's key science enterprises. In addition to
searching the universe for life, its goal is to understand how our present-day
universe evolved from the Big Bang.
The Miller-Urey Experiment - (Web Link 30-3) An interview with Professor Stanley Miller, a
pioneer of experimental research into the origin of life.
Extremophiles - (Web Link 30-4) This Scientific American article by Michael T. Madigan and Barry
L. Marrs describes microbes which thrive under conditions that would kill other
creatures.
The Search for Extreme Life - (Web Link 30-4) An interview with Baruch S. Blumberg, first head
of NASA's Astrobiology Institute, discusses his research into exotic microorganisms.
The Nine Planets: Europa - (Web Link 30-5) Information, images, and links to additional resources about Europa.
Galileo Observes Europa A summary of Galileo observations of Europa. - (Web Link 30-5)
Chaotic Terrain on Europa - (Web Link 30-5) A collection of Galileo images of Europa's ice rafts
and other chaotic terrain. Ridges and Fractured Terrain on Europa - A collection of Galileo images of Europa's fractured surface.
Europa Orbiter - (Web Link 30-5) This site describes a proposed NASA mission to place a
spacecraft into orbit around Europa. Viking Landers Links to the full story of the Viking 1 and Viking 2 landers and
the discoveries they made:
On Mars: Exploration of the Red Planet 1958-1978 - (Web Link 30-6) The official NASA history, with emphasis on the Viking missions.
Beagle 2 - (Web Link 30-7) is the British-led effort to place a lander on Mars as part of the
European Space Agency's Mars Express mission to be launched in June 2003.
Mars Express - (Web Link 30-7) This ESA web site describes the first European mission to Mars. The "Face on Mars" Information about a geological feature on the Martian
surface that was interpreted by some to be an image of a face.
The "Happy Face" on Mars - (Web Link 30-8) An image from the Mars Global Surveyor spacecraft
shows a crater that resembles a "happy face" icon.
Planetary Science Research Discoveries ‹ Martian Meteorites - (Web Link 30-9) This extensive NASA-sponsored web site includes at least ten articles about Martian
meteorites. These present the evidence both for and against the idea that fossil
microorganisms have been found in these meteorites.
Magnetotactic Bacteria and Ancient Life on Mars - (Web Link 30-9) A re-analysis of the
Martian meteorite ALH 84001 finds evidence for magnetite crystals of a type
produced only by a biological process unique to magnetotactic bacteria. The Roswell Alien "Cover-Up" Two articles from The Skeptical Inquirer provide
simple explanations for the 1947 UFO "crash landing" in Roswell, New Mexico.
Alas, no aliens were involved.
The "Alien Autopsy" Hoax - (Web Link 30-10) Did scientists perform an autopsy on an alien that
crash-landed in New Mexico in 1947? A film shown on various television programs
claims to show this autopsy. This web site provides compelling evidence that the
film is a hoax.
Where Are They? - (Web Link 30-11) This Scientific American article by astrophysicist Ian Crawford
explores the question of how many civilizations might inhabit our Milky Way
Galaxy.
SETI at the University of California, Berkeley - (Web Link 30-12)
SETI@home - (Web Link 30-13) is a scientific experiment that uses Internet-connected computers in
the search for extraterrestrial intelligence. You can participate by running a free
program that downloads and analyzes radio telescope data.