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Crew news conference
The five crew members aboard the International Space Station answer questions during this in-flight news conference from Wednesday, Oct. 20. (29min 26sec file)
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San Fran. interview
Expedition 10 commander Leroy Chiao and Expedition 9 flight engineer Michael Fincke answer questions from a reporter with KPIX television in San Francisco. (8min 52sec file)
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CBS Radio interview
CBS Radio's Peter King and Bill Harwood chat with space station astronauts Leroy Chiao and Michael Fincke during the handover activities between Expedition crews. (11min 06sec file)
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Expedition 9 review
This narrated movie provides a look back at the six-month Expedition 9 mission aboard the International Space Station with commander Gennady Padalka and flight engineer Michael Fincke. (8min 24sec file)
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Soyuz docking
The Russian Soyuz TMA-5 capsule successfully docks to the International Space Station, delivering the Expedition 10 crew for its half-year mission. (3min 21sec file)
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Docking in full
This longer-length broadband clip follows the Soyuz TMA-5 capsule's approach and docking to the station's Pirs module. (8min 47sec file)
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Post-docking news conference
Russian and U.S. space officials hold a post-docking press conference from the mission control center outside Moscow. (23min 04sec file)
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Launch of Expedition 10
The Russian Soyuz rocket blasts off from Baikonur Cosmodrome carrying the Expedition 10 crew International Space Station for a six-month mission. (2min 25sec file)
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Launch in full
This longer-length broadband clip follows the launch of Expedition 10 from the final minute of the countdown through deployment of the Soyuz capsule from the third stage. (10min 15sec file)
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The State Commission
The State Commission hears from senior Russian and American officials before giving final approval to launch Expedition 10 to the International Space Station. (13min 46sec file)
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New view of the sky
Posted: October 20, 2004

Astronomers using the National Science Foundation's Very Large Array (VLA) have overcome longstanding technical hurdles to map the sky at little-explored radio frequencies that may provide a tantalizing look deep into the early Universe. The scientists have released images and data covering half of the sky visible from the VLA, and hope to complete their survey within a year.

A "rogues' gallery" of radio galaxy types seen in the VLSS. White regions indicate radio-bright emitting regions in the galaxies, while deep red/black indicate regions of little or no radio emission. In all cases, the radio galaxies are thought to shine because of jets of highly relativistic material being shot from the environment of a supermassive black hole in the center of the radio galaxy. The diversity of shapes probably reflects the environment of the radio galaxy itself as well as the history of the supermassive black hole and how much material has fallen into it. Credit: NRAO/AUI/NSF
The VLA Low-frequency Sky Survey (VLSS) is producing sky images made at an observing frequency of 74 MHz, a far lower frequency than used for most current radio-astronomy research.

"Because of the Earth's ionosphere, such a low frequency has proven very difficult for high-quality imaging, and it is only in the past few years that we have developed the techniques that make a project like the VLSS possible," said Rick Perley, of the National Radio Astronomy Observatory (NRAO) in Socorro, NM.

Because the high-quality VLSS images will give astronomers a look at the Universe through what essentially is a new "window," they expect the images to reveal some rare and important objects.

"We expect to find very distant radio galaxies -- galaxies spewing jets of material at nearly light speed and powered by supermassive black holes," said Joseph Lazio of the Naval Research Laboratory in Washington, DC. "By determining just how distant these radio galaxies are, we will learn how early the black holes formed in the history of the Universe," he added.

Another tantalizing possibility is that the low-frequency images may reveal "halos" and "relics" produced by collisions of galaxies in clusters. If the halos and relics are found in the distant, and thus early, Universe, it will give scientists important clues about the timetable for formation of large-scale structure. In addition, the astronomers hope that the VLSS images may show previously-undiscovered pulsars -- superdense, spinning neutron stars.

Massive planets -- "super Jupiters" circling stars beyond the Sun -- also might reveal themselves through bursts of radio emission at the frequency of this survey, the astronomers speculated.

Images from the survey are being made available to other scientists as soon as they are completed. The survey will use some 800 hours of VLA observing time. The newly-released images and data are available via the NRAO Web site.

"By doing this survey and making the results available, we are bringing low-frequency radio data, previously quite difficult to produce, to all astronomers in a simple and easy manner," Perley said.

"We also expect that this survey will spur additional research into objects that scientists find puzzling or interesting," Perley saidd. "We really will have to wait for years to know the full scientific benefit of this survey," he said.

In addition to Perley and Lazio, the VLSS team includes James Condon and William Cotton of NRAO; Aaron Cohen and Wendy Lane of the National Research Council and the Naval Research Laboratory; Namir Kassim of the Naval Research Laboratory; and William Erickson of the University of Maryland and University of Tasmania.

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement with Associated Universities, Inc.