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Universe's end frozen in time HARVARD-SMITHSONIAN CENTER FOR ASTROPHYSICS RELEASE Posted: December 13, 2001 Astronomers often investigate the beginning of the Universe, starting with the Big Bang. New data is shedding light on the opposite end of the arrow of time - how the Universe might end. In the past, astronomers have theorized about what we might see if we watched the Universe billions of years from now. Some thought the expansion of the universe would slow and reverse, compressing all matter back in a "Big Crunch." Others said the expansion would continue forever and we would see the stars in all the galaxies age and die, leaving us in darkness. But now, a calculation by Professor Abraham Loeb, a theoretical astrophysicist at the Harvard-Smithsonian Center for Astrophysics, paints a different picture regarding the fate of the universe, and it looks quite lonely. As the universe ages and expands, fewer and fewer galaxies will be visible to us. Even weirder, as we watch the galaxies fade, their appearance will freeze in time. No matter how long we watch, like celluloid heroes in the cinema, they will never grow older or change. They will only grow dimmer as they recede from us.
Over the next 100 billion years, this accelerating force will shrink our cosmic horizon, reducing the number of galaxies we can see to only about a thousand members of the local Virgo Cluster and surrounding areas. As distant galaxies cross our horizon, their image will get frozen. The light they emit after the moment of horizon crossing will never be able to reach us. "This process is analogous to what you see if you watch a light source fall into a black hole," states Loeb. "As an object crosses the black hole's event horizon, its image seems to freeze and fade away because you can't see the light it emits after that point." Similarly, we will see distant galaxies freeze into an unchanging vista. We will never see new stars being born or old stars dying. The galactic snapshots will simply fade away to invisibility. This has grim consequences for our study of the universe. Not only will the number of galaxies we can see shrink away, but we will not be able to watch the evolution of these galaxies later in their history. The amount of information available to us about the distant universe is finite. For example, light from the most distant quasar yet seen left that quasar when the universe was only a billion years old. (The universe is now estimated to be 14 billion years old.) Loeb's calculations show that if we watch this quasar for the next several billion years, we will see it freeze at an age of six billion years and stop changing. Its frozen image will only grow fainter as the universe expands. Headquartered in Cambridge, Massachusetts, the Harvard-Smithsonian
Center for Astrophysics (CfA) is a joint collaboration between the
Smithsonian Astrophysical Observatory and the Harvard College
Observatory. CfA scientists organized into seven research divisions
study the origin, evolution, and ultimate fate of the universe.
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On to Mars A wide variety of papers presented at the first four years of the Mars Society's annual conference are collected together in this volume.Apollo 12 tribute DVD set ![]() New! Featuring the jovial crew of Pete Conrad, Dick Gordon and Alan Bean, the Apollo 12 mission was struck by lightning shortly after liftoff but proceeded on the second successful exploration voyage to the lunar surface. This three-disc DVD brings the mission to life with extraordinary detail. U.S. - U.K. - E.U. - Worldwide Fallen Heroes special patch This special 12-inch embroidered patch commemorates the U.S. astronauts who made the ultimate sacrifice, honoring the crews of Apollo 1, Challenger and Columbia.U.S. - U.K. - E.U. - Worldwide Women in Space Women of Space: Cool Careers on the Final Frontier is for girls, young women, and anyone else interested in learning about exciting careers in space exploration. Includes CD-ROM.U.S. - U.K. - E.U. - Worldwide Mars rover poster This new poster features some of the best pictures from NASA's amazing Mars Exploration Rovers Spirit and Opportunity.U.S. Apollo 11 special patch Special collectors' patch marking the 35th anniversary of the historic Apollo 11 moon landing is now available.U.S. - U.K. Current Shuttle Mission Patch Free shipping to U.S. addresses! The official embroidered patch for shuttle Endeavour's flight to launch the Tranquility module and cupola to the space station now available in our store!Expedition 20 The official embroidered patch for the International Space Station Expedition 20 crew is now available from our stores.![]() Ares Patch The Ares Project will develop two new rockets to launch astronauts back to the Moon under NASA's Vision for Exploration. The Ares 1 will employ a single space shuttle solid rocket booster to loft the Orion crew capsule. The gigantic Ares 5 will haul the equipment and cargo needed for such lunar voyages. This is the Ares emblem.One Giant Leap
Hosted by Corbin Bernsen, this award winning documentary marks the 50th anniversary of the U.S. space agency and features exclusive interviews with veteran astronauts.Expedition 21 The official embroidered patch for the International Space Station Expedition 21 crew is now available from our stores.The web's best space video service! Get additional video, audio, image and virtual reality content for a low-cost monthly or annual subscription fee. Subscriptions start at $5.95/£3.50. Click here to see what's currently available. Hubble Posters Stunning posters featuring images from the Hubble Space Telescope and world-renowned astrophotographer David Malin are now available from the Astronomy Now Store.Get e-mail updates Sign up for our NewsAlert service and have the latest news in astronomy and space e-mailed direct to your desktop (privacy note: your e-mail address will not be used for any other purpose). Station Calendar
NEW! This beautiful 12" by 12" wall calendar features stunning images of the International Space Station and of the people, equipment, and space craft associated with it, as it takes shape day by day in orbit high above the Earth. |
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