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Riding on Endeavour

Now you can take a virtual trip aboard shuttle Endeavour's recent launch thanks to video cameras mounted inside the ship's cockpit as well as outside on the twin solid rocket boosters and external tank.

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Launch of Phoenix

The Phoenix lander bound for the northern plains of Mars is launched atop a Delta 2 rocket from Cape Canaveral.

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Phoenix animation

Project officials narrate animation of Phoenix's launch from Earth, arrival at Mars, touchdown using landing rockets and the craft's robot arm and science gear in action.

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"The Time of Apollo"

This stirring 1970s documentary narrated by Burgess Meredith pays tribute to the grand accomplishments of Apollo as men left Earth to explore the Moon and fulfill President Kennedy's challenge to the nation.

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"Apollo 17: On The Shoulders of Giants"

Apollo's final lunar voyage is relived in this movie. The film depicts the highlights of Apollo 17's journey to Taurus-Littrow and looks to the future Skylab, Apollo-Soyuz and shuttle programs.

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"Apollo 10: To Sort Out The Unknowns"

The May 1969 mission of Apollo 10 served as a final dress rehearsal before the first lunar landing later that summer. Stafford, Young and Cernan went to the moon to uncover lingering spacecraft problems that needed to be solved.

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Traveling on Freedom 7

Fly with Alan Shepard during his historic journey into space with this documentary that takes the viewer along as an invisible companion to America's first astronaut.

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'Lego-block' galaxies found in early universe
NASA NEWS RELEASE
Posted: September 6, 2007


In this image of the Hubble Ultra Deep Field, several objects are identified as the faintest, most compact galaxies ever observed in the distant universe. They are so far away that we see them as they looked less than one billion years after the Big Bang. Credit: NASA/STScI/ESA
 
NASA's Hubble and Spitzer space telescopes have joined forces to discover nine of the smallest, faintest, most compact galaxies ever observed in the distant universe. Blazing with the brilliance of millions of stars, each of the newly discovered galaxies is 100 to 1,000 times smaller than our Milky Way galaxy.

"These are among the lowest mass galaxies ever directly observed in the early universe," said Nor Pirzkal of the Space Telescope Science Institute in Baltimore, Md.

The conventional model for galaxy evolution predicts that small galaxies in the early universe evolved into the massive galaxies of today by coalescing. These nine Lego-like "building block" galaxies initially detected by Hubble likely contributed to the construction of the universe as we know it.

Pirzkal was surprised to find that the galaxies' estimated masses were so small. Hubble's cousin observatory, Spitzer, was called upon to make precise determinations of their masses. The Spitzer observations confirmed that these galaxies are some of the smallest building blocks of the universe.

These young galaxies offer important new insights into the universe's formative years, just one billion years after the Big Bang. Hubble detected sapphire blue stars residing within the nine pristine galaxies. The youthful stars are just a few million years old and are in the process of turning Big Bang elements, primarily hydrogen and helium, into heavier elements. The stars have probably not yet begun to pollute the surrounding space with elemental products forged within their cores.

"While blue light seen by Hubble shows the presence of young stars, it is the absence of red light in the sensitive Spitzer images that was conclusive in showing that these are truly young galaxies without an earlier generation of stars," says Sangeeta Malhotra of Arizona State University in Tempe, Ariz., one of the investigators.

The galaxies were first identified by James Rhoads of Arizona State University and Chun Xu of the Shanghai Institute of Technical Physics in Shanghai, China, by their prominent and energetic light coming from glowing hydrogen. Three of the galaxies appear to be slightly disrupted; rather than being shaped like rounded blobs, they appear stretched into tadpole-like shapes. This is a sign that they may be interacting and merging with neighboring galaxies to form larger, cohesive structures.

The galaxies were observed in the well-known Hubble Ultra Deep Field with Hubble's Advanced Camera for Surveys and the Near Infrared Camera and Multi-object Spectrometer. Observations were also done with Spitzer's Infrared Array Camera and the European Southern Observatory's Infrared Spectrometer and Array Camera.

Pirzkal's main collaborators were Malhotra, Rhoads, Xu and the Grism Advanced Camera for Surveys Program for Extragalactic Science team.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. The Space Telescope Science Institute conducts Hubble science operations. The institute is operated for NASA by the Association of Universities for Research in Astronomy, Inc., Washington.