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'Salute to Titan'
This video by Lockheed Martin relives the storied history of the Titan rocket family over the past five decades. (4min 21sec file)
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Titan history
Footage from that various Titan rocket launches from the 1950s to today is compiled into this movie. (6min 52sec file)
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Soyuz's fiery re-entry
A camera aboard the space station captured this extraordinary video of the Soyuz TMA-5 capsule plunging back to Earth. The descent module with the crew is seen flying onward while the discarded docking and propulsion modules are ripped apart in the atmosphere. (2min 21sec file)
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Expedition 10 undocking
The Soyuz TMA-5 capsule undocks from the space station's Zarya module to ferry the Expedition 10 crew back to Earth. (5min 02sec file)
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Expedition 10 farewell
The Expedition 10 crew says farewell to the new space station crew and heads into the Soyuz capsule in advance of departure. (3min 50sec file)
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ISS command change
The Expedition 10 crew hands command of the International Space Station to the Expedition 11 crew in this ceremony staged in the Destiny module on April 22. (1min 49sec file)
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Griffin goes before press
Michael Griffin, NASA's new administrator, holds his first news conference from agency headquarters to discuss shuttle return to flight, exploration plans and Hubble servicing. (46min 44sec file)
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NASA's new boss
During his first day on the job, Michael Griffin, NASA's new administrator, addresses agency employees and answers questions on a variety of topics on April 14. (28min 50sec file)
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Griffin in his own words
Nominated to become the new administrator of NASA, Michael Griffin gives an opening statement to a Senate committee about his thoughts on the agency. (6min 38sec file)
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Senators quiz Griffin
Senators ask a wide range of questions to NASA administrator nominee Michael Griffin concerning the future exploration, the space shuttle and space station programs, Hubble servicing options and aeronautics funding. (27min 06sec file)
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'Wonderful' star reveals its hot nature
CHANDRA X-RAY CENTER NEWS RELEASE
Posted: April 28, 2005

For the first time an X-ray image of a pair of interacting stars has been made by NASA's Chandra X-ray Observatory.


The Chandra image shows Mira A (right), a highly evolved red giant star, and Mira B (left), a white dwarf. To the right of the image is an artist's conception of the Mira star system. Mira A is losing gas rapidly from its upper atmosphere via a stellar wind. Mira B exerts a gravitational tug that creates a gaseous bridge between the two stars. Gas from the wind and bridge accumulates in an accretion disk around Mira B and collisions between rapidly moving particles in the disk produce X-rays. Credit: X-ray: NASA/CXC/SAO/M. Karovska et al.; Illustration: CXC/M.Weiss
 
The ability to distinguish between the interacting stars - one a highly evolved giant star and the other likely a white dwarf - allowed a team of scientists to observe an X-ray outburst from the giant star and find evidence that a bridge of hot matter is streaming between the two stars.

"Before this observation it was assumed that all the X-rays came from a hot disk surrounding a white dwarf, so the detection of an X-ray outburst from the giant star came as a surprise," said Margarita Karovska of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., and lead author article in the latest Astrophysical Journal Letters describing this work. An ultraviolet image made by the Hubble Space Telescope was a key to identifying the location of the X-ray outburst with the giant star.

X-ray studies of this system, called Mira AB, may also provide better understanding of interactions between other binary systems consisting of a "normal" star and a collapsed star such as a white dwarf, black hole or a neutron star, where the individual stellar objects and gas flow cannot be distinguished in an image.

The separation of the X-rays from the giant star and the white dwarf was made possible by the superb angular resolution of Chandra, and the relative proximity of the star system at about 420 light years from Earth. The stars in Mira AB are about 6.5 billion miles apart, or almost twice the distance of Pluto from the Sun.

Mira A (Mira) was named "The Wonderful" star in the 17th century because its brightness was observed to wax and wane over a period of about 330 days. Because it is in the advanced, red giant phase of a star's life, it has swollen to about 600 times that of the Sun and it is pulsating. Mira A is now approaching the stage where its nuclear fuel supply will be exhausted, and it will collapse to become a white dwarf.

The internal turmoil in Mira A could create magnetic disturbances in the upper atmosphere of the star and lead to the observed X-ray outbursts, as well as the rapid loss of material from the star in a blustery, strong, stellar wind. Some of the gas and dust escaping from Mira A is captured by its companion Mira B.

In stark contrast to Mira A, Mira B is thought to be a white dwarf star about the size of the Earth. Some of the material in the wind from Mira A is captured in an accretion disk around Mira B, where collisions between rapidly moving particles produce X-rays.

One of the more intriguing aspects of the observations of Mira AB at both X-ray and ultraviolet wavelengths is the evidence for a faint bridge of material joining the two stars. The existence of a bridge would indicate that, in addition to capturing material from the stellar wind, Mira B is also pulling material directly off Mira A into the accretion disk.

Chandra observed Mira with its Advanced CCD Imaging Spectrometer on December 6, 2003 for about 19 hours. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for NASA's Science Mission Directorate, Washington. Northrop Grumman of Redondo Beach, Calif., was the prime development contractor for the observatory. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass.