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Launch of SpaceShipOne
Watch the hair-raising flight of SpaceShipOne during the first of two launches needed to win the $10 million X Prize. The craft experienced a major rolling motion and early engine shutdown. (3min 40sec file)
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The roll close up
This high bandwidth clip focuses on the unplanned rolling motion that SpaceShipOne saw during its engine firing. (1min 25sec file)
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Reentry descent
SpaceShipOne feathers its wings for a "care-free" reentry into Earth's atmosphere that doesn't require a precise angle of attack. (2min 59sec file)
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SpaceShipOne landing
SpaceShipOne glides to landing on the runway at Mojave airport under the control of astronaut Mike Melvill. (1min 41sec file)
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Melvill emerges
A truck tows SpaceShipOne from the runway to the spectator viewing spot where Mike Melvill climbs out for welcoming by Burt Rutan and others. (2min 01sec file)
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Post-flight speeches
Hear from Mike Melvill, Burt Rutan and others during post-flight speeches on the runway at Mojave airport. (6min 40sec file)
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X-43A test
NASA's X-43A research craft and its Pegasus rocket booster complete a captive carry test flight aboard a B-52 launch aircraft. (1min 48sec file)
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See the KSC damage
See damage to the Vehicle Assembly Building, the Saturn 5 Center and other facilities at Kennedy Space Center caused by Hurricane Jeanne. (4min 31sec file)
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Cape damage report
Jim Kennedy, director of the Kennedy Space Center, and Col. Mark Owen, 45th Space Wing commander, hold a news conference on Monday, Sept. 27 to provide a preliminary report on damage from Hurricane Jeanne at KSC and Cape Canaveral Air Force Station. (49min 30sec file)
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Hurricane Jeanne
Cameras aboard the International Space Station captured these views of Hurricane Jeanne on Saturday, Sept. 25 as the storm approached Florida. (3min 59sec file)
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Station news briefing
International Space Station program manager Bill Gerstenmaier holds a news conference Sept. 24 to discuss problems with the oxygen generation system and Expedition 10 launch preparations. (44min 06sec file)
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Galaxy clusters collide
Scientists describe a cosmic hurricane in this news conference from Sept. 23, explaining how two merging galaxy clusters churn high-pressure shock waves that leave thousands of galaxies strewn in the wake. (53min 24sec file)
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Scientists say supernova explosions imminent
Posted: September 30, 2004

Three powerful recent blasts from three wholly different regions in space have left scientists scrambling. The blasts, which lasted only a few seconds, might be early alert systems for star explosions called supernovae, which could start appearing any day.

The first two blasts, called X-ray flashes, occurred on September 12 and 16. These were followed by a more powerful burst on September 24. The burst seems to be on the cusp between an X-ray flash and a full-fledged gamma ray burst, a discovery interesting in its own right. If these signals lead to supernovae, as expected, scientists would have a tool to predict star explosions, and researchers could watch explosions from start to finish.

A team led by Dr. George Ricker of the Massachusetts Institute of Technology (MIT), Cambridge, detected the explosions with NASA's High-Energy Transient Explorer (HETE-2). Science teams around the world, using space- and ground-based observatories, have joined in, torn and conflicted over which burst region to track most closely.

"Each burst has been beautiful," Ricker said. "Depending on how these evolve, they could support important theories about supernovae and gamma-ray bursts. These past two weeks have been like 'cock, fire, reload.' Nature keeps on delivering, and our HETE-2 satellite keeps on responding flawlessly," he said."

Gamma ray bursts are the most powerful explosions known other than the Big Bang. Many appear to be caused by the death of a massive star collapsing into a black hole. Others might be from merging black holes or neutron stars. In either case, the event likely produces twin, narrow jets in opposite directions, which carry off tremendous amounts of energy. If one of jets points to Earth, we see this energy as a gamma ray burst.

The lower-energy X-ray flashes might be gamma ray bursts viewed slightly off angle from the jet direction, somewhat similar to how a flashlight is less blinding when viewed at an angle. The majority of light particles from X-ray flashes, called photons, are X-rays, energetic, but not quite as powerful as gamma rays. Both types of bursts last only a few milliseconds to about a minute. HETE-2 detects the bursts, studies their properties, and provides a location, so other observatories can study the burst afterglow in detail.

The trio of bursts from the past few weeks has the potential of settling two long-standing debates. Some scientists say X-ray flashes are different beasts all together, not related to gamma-ray bursts and massive star explosions. Detecting a supernova in the region where the X-ray flash appeared would refute that belief, instead confirming the connection between the two. Follow-up observations of the September 24 burst, named GRB040924 for the date it was observed, are already solidifying the theory of a cosmic explosion continuum from X-ray flashes up through gamma ray bursts.

More interesting for supernova hunters is the fact X-ray flashes are closer to Earth than gamma ray bursts. While the connection between gamma ray bursts and supernovae has been made, these supernovae are too distant to study in detail. X-ray flashes might be signals for supernovae; scientists can actually sink their teeth into and observe in detail.

"Last year HETE-2 sealed the connection between gamma ray bursts and massive supernovae," said Prof. Stanford Woosley of the University of California at Santa Cruz, who has championed several theories concerning the physics of star explosions. "These two September bursts may be the first time we see an X-ray flash lead to a supernova."

"We all expect much more of this type of exciting science to come after the launch of Swift," said Dr. Anne Kinney, director of NASA's Universe Division. The Swift spacecraft, scheduled to launch no earlier than late October, contains three telescopes (gamma ray, X-ray and UV/optical) for quick burst detection and immediate follow-up observations of the afterglow.

HETE was built by MIT as a mission of opportunity under the NASA Explorer Program. It was built in collaboration among U.S. universities, Los Alamos National Laboratory, N.M., scientists and organizations in Brazil, France, India, Italy and Japan.