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Discovery crew's movies
The seven astronauts of space shuttle Discovery's return to flight mission recently gathered for a public celebration of their mission. They narrated an entertaining movie of highlights and personal footage taken during the mission.

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GPS satellite launched
The Boeing Delta 2 rocket roars off Cape Canaveral's launch pad 17A carrying the first modernized Global Positioning System satellite for the U.S. Air Force.

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Back to the Moon!
NASA unveils the agency's blueprint for building the future spacecraft and launch vehicles needed for mankind's return to the lunar surface in the next decade.

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Distant space explosion
Astronomers announce the detection by NASA's Swift satellite of the most distant explosion yet, a gamma-ray burst from the edge of the visible universe, during this media teleconference held Monday, September 12. (54min 01sec file)

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Hill-climbing Mars rover
The Mars Exploration Rover Spirit has reached the summit of Husband Hill, returning a spectacular panorama from the hilltop in the vast Gusev Crater. Scientists held a news conference Sept. 1 to reveal the panorama and give an update on the twin rover mission.

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Planes track Discovery
To gain a new perspective on space shuttle Discovery's ascent and gather additional imagery for the return to flight mission, NASA dispatched a pair of high-flying WB-57 aircraft equipped with sharp video cameras in their noses.

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Rocket booster cams
When space shuttle Discovery launched its two solid-fuel booster rockets were equipped with video cameras, providing dazzling footage of separation from the external fuel tank, their free fall and splashdown in the sea.

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Discovery ferried home
Mounted atop a modified Boeing 747, space shuttle Discovery was ferried across the country from Edwards Air Force Base, California, to Kennedy Space Center, Florida.

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Shuttle tank returned
Shuttle fuel tank ET-119 is loaded onto a barge at Kennedy Space Center for the trip back to Lockheed Martin's Michoud Assembly Facility in New Orleans. The tank will be used in the investigation to determine why foam peeled away from Discovery's tank on STS-114 in July.

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Delta 4 launch delayed
Launch of the GOES-N weather observatory aboard a Boeing Delta 4 rocket is postponed at Cape Canaveral, Florida.

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Mars probe leaves Earth
The Mars Reconnaissance Orbiter lifts off aboard a Lockheed Martin Atlas 5 rocket from Cape Canaveral's Complex 41.

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Unusual meteorite unlocks treasure trove of secrets
FLORIDA STATE UNIVERSITY NEWS RELEASE
Posted: September 28, 2005

An unusual meteorite that fell on a frozen lake in Canada five years ago has led a Florida State University geochemist to a breakthrough in understanding the origin of the chemical elements that make up our solar system.

Professor Munir Humayun of the National High Magnetic Field Laboratory and the geological sciences department at FSU and Alan Brandon of NASA discovered an isotopic anomaly in the rare element osmium in primitive meteorites. The anomalous osmium was derived from small stars with a higher neutron density than that which formed our solar system. The findings of the researchers, who also included colleagues from the University of Maryland and Bern University in Switzerland, were recently published in the journal Science.

"Our new data enabled us to catch a glimpse of the different star types that contributed elements to the solar system, the parental stars of our chemical matter," Humayun said. "It opens a treasure trove of prospects for exploring the formation of the elements."

For about 50 years, scientists have known that all the elements beyond iron in the periodic table were made in stars by up to three nuclear processes. Osmium is mainly formed by two of those processes, the so-called s-process in which neutrons are slowly added to nuclei over a period of perhaps thousands of years in aging, medium-size stars and the r-process that occurs in supernovae in which neutrons are pumped into nuclei at a rate of hundreds of neutrons in a few seconds.

The new data gathered by Humayun's team not only shows the different star types that contribute elements to the solar system, it also will be used to test astrophysical models of production of the chemical elements at a more sophisticated level than previously possible, he said.

Humayun and colleagues studied samples from an extremely fragile meteorite that fell on Tagish Lake on Jan. 18, 2000. Unlike iron meteorites, primitive meteorites like this one are not preserved long on the Earth's surface because they disintegrate and form mud when exposed to water. This one was retrieved within 48 hours of its fall in the dead of an Arctic winter.

Most meteorites have a uniform osmium isotopic distribution, but Humayun's team found that osmium extracted from the Tagish Lake meteorite was deficient in s-process osmium. They are the first to report an anomaly in the isotopic makeup of the element osmium from meteorites.

Other researchers have found isotope anomalies in several other elements in some primitive meteorites, but not in others. Because of the disparity, scientists believed that the ashes of stars that preceded the solar system must have been sprinkled in a non-uniform way into the solar nebula, the disk of gas and dust that formed the sun, planets and meteorites. Scientists had hypothesized that some of the dust could have been created by an active nearby star.

Humayun's findings challenge that explanation. He believes that the anomaly is an expression of presolar stardust that survived the homogenization that affected nearly all other meteorites. Typically, stardust accretes to form meteorites and is then heated by radioactivity - a process that destroys the silicon carbide grains that are the carriers of the anomaly. But in the case of the meteorites with osmium isotopic anomalies, the heat was not significant enough to destroy the silicon carbide.

"The previous interpretation of incomplete mixing of different sources of dust at the scale of the solar nebula no longer seems tenable," he said. "We now interpret those anomalies as incomplete dissolution of silicon carbide grains that carried traces of molybdenum, ruthenium and osmium. These anomalies reveal that the raw materials from which our solar system was built are preserved in a few exceptional meteorites, from which we can now recover the prehistory of our solar system."

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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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