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Apollo 11 returns
Apollo 11 safely returns to Earth, making a parachute-assisted splashdown in the ocean. (3min 57sec file)
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MESSENGER preview
Mission officials and scientists preview the flight of NASA's MESSENGER space probe to orbit the planet Mercury during this news conference. (41min 36sec file)
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Apollo 11 moonwalk
Armstrong and Aldrin gather lunar samples and conduct experiments during their moonwalk. (2min 27sec file)
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Moon landing explained
The Apollo 11 astronauts narrate footage of their historic landing on the moon and describe the technical details of the descent. (22min 02sec file)
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Leaving the moon
The Eagle lunar module returns to the orbiting command module and the Apollo 11 astronauts head back to Earth. (5min 33sec file)
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Anniversary celebration
The Apollo 11 astronauts and other dignitaries hold a special 35th anniversary celebration in Washington on July 20. Hear from Armstrong, Aldrin, Collins, Walter Cronkite, NASA Administrator O'Keefe and others. (76min 12sec file)
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Heading for landing
The "Eagle" lunar lander undocks from the "Columbia" command module in preparation for landing. (1min 21sec file)
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The Eagle has landed!
The Apollo 11 spacecraft "Eagle" lands on the Moon 35 years ago, delivering Armstrong and Aldrin. (2min 04sec file)
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Walking on the moon
Neil Armstrong and Buzz Aldrin step foot on the surface of the moon on July 20 1969, forever changing history. (11min 17sec file)
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Shuttle engine test
One of the liquid-fueled main engines that will power space shuttle Discovery on the return-to-flight mission next spring is test-fired at NASA's Stennis Space Center. (1min 56sec file)
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Cronkite interview
Famed CBS News anchorman Walter Cronkite recalls the Apollo 11 mission in this interview on NASA Television. (3min 15sec file)
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Apollo 11 crew interview
An interview with astronauts Neil Armstrong, Michael Collins and Buzz Aldrin takes viewers in a retrospective through the Apollo 11 mission. (30min 39sec file)
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A day in the lives of galaxies
SPACE TELESCOPE SCIENCE INSTITUTE NEWS RELEASE
Posted: July 23, 2004

Like a photographer clicking random snapshots of a crowd of people, NASA's Hubble Space Telescope has taken a view of an eclectic mix of galaxies. In taking this picture, Hubble's Advanced Camera for Surveys was not looking at any particular target. The camera was taking a picture of a typical patch of sky, while Hubble's infrared camera was viewing a target in an adjacent galaxy-rich region.


Credits: NASA, ESA, J. Blakeslee and H. Ford (Johns Hopkins University)
Download a larger image version here

 
The jumble of galaxies in this image, taken in September 2003, includes a yellow spiral whose arms have been stretched by a possible collision [lower right]; a young, blue galaxy [top] bursting with star birth; and several smaller, red galaxies.

But the most peculiar-looking galaxy of the bunch -- the dramatic blue arc in the center of the photo -- is actually an optical illusion. The blue arc is an image of a distant galaxy that has been smeared into the odd shape by a phenomenon called gravitational lensing. This "funhouse- mirror effect" occurs when light from a distant object is bent and stretched by the mass of an intervening object.

In this case the gravitational lens, or intervening object, is a red elliptical galaxy nearly 6 billion light-years from Earth. The red color suggests that the galaxy contains older, cooler stars.

The distant object whose image is smeared into the long blue arc is about 10 billion light-years away. This ancient galaxy existed just a few billion years after the Big Bang, when the universe was about a quarter of its present age. The blue color indicates that the galaxy contains hot, young stars.

Gravitational lenses can be seen throughout the sky because the cosmos is crowded with galaxies. Light from distant galaxies, therefore, cannot always travel through space without another galaxy getting in the way. It is like walking through a crowded airport. In space, a faraway galaxy's light will travel through a galaxy that is in the way. But if the galaxy is massive enough, its gravity will bend and distort the light.

Long arcs, such as the one in this image, are commonly seen in large clusters of galaxies because of their huge concentrations of mass. But they are not as common in isolated galaxies such as this one. For the gravitational lens to occur, the galaxies must be almost perfectly aligned with each other.

Gravitational lenses yield important information about galaxies. They are a unique and extremely useful way of directly determining the amount of mass, including dark matter, in a galaxy. Galaxies are not just made up of stars, gas, and dust. An invisible form of matter, called dark matter, makes up most of a galaxy's mass. A study of this newly discovered system, dubbed J033238-275653, was published in the Astrophysical Journal Letters. This study, together with similar observations, may allow astronomers to make the first direct measurements of the masses of bright, nearby galaxies.

The Space Telescope Science Institute (STScI) is operated by the Association of Universities for Research in Astronomy, Inc. (AURA), for NASA, under contract with the Goddard Space Flight Center, Greenbelt, MD. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency (ESA).

Ares 1-X Patch
The official embroidered patch for the Ares 1-X rocket test flight, is available for purchase.
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Apollo Collage
This beautiful one piece set features the Apollo program emblem surrounded by the individual mission logos.
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Expedition 21
The official embroidered patch for the International Space Station Expedition 21 crew is now available from our stores.
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Hubble Patch
The official embroidered patch for mission STS-125, the space shuttle's last planned service call to the Hubble Space Telescope, is available for purchase.
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