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Life on the station
NASA astronauts Bill McArthur and John Phillips chat with Associated Press space reporter Marcia Dunn about life aboard the International Space Station in this live space-to-Earth interview from the Destiny laboratory module on October 5.

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West Coast Delta 4
In preparation for the West Coast launch of Boeing's next-generation Delta 4 rocket, the two-stage vehicle is rolled out of its horizontal hangar and driven to the Space Launch Complex-6 pad for erection. The nose cone for the NRO payload is then brought to the pad.

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West Coast shuttle
Boeing's Delta 4 rocket pad at Vandenberg Air Force Base was renovated in recent years, transforming Space Launch Complex-6 from the West Coast space shuttle launch site into a facility for the next-generation unmanned booster. This collection of footage shows the 1985 launch pad test using NASA's orbiter Enterprise.

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News briefing from ISS
The Expedition 11 and Expedition 12 crews, along with space tourist Greg Olsen, hold a live news conference with American and Russian reporters on October 4. (26min 36sec file)

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Next ISS crew lifts off
A Russian Soyuz spacecraft safely launched from Baikonur Cosmodrome Friday night with the International Space Station's twelfth resident crew and a paying tourist aboard.

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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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New optics produce ultrasharp images of sunspot
Posted: October 5, 2005

Advanced technologies now available at the National Science Foundation's Dunn Solar Telescope at Sunspot, New Mexico, are revealing striking details inside sunspots and hint at features remaining to be discovered in solar activity.

High-resolution image of sunspot produced with the new camera attached to the Dunn's adaptive optics system. Credit: Friedrich Woeger, KIS, and Chris Berst and Mark Komsa, NSO/AURA/NSF
This image, spanning an area more than three times wider than Earth, was made possible by the Dunn's recently completed AO76 advanced adaptive optics image correction system and a new high-resolution CCD camera.

The Dunn is the nation's premier high-resolution solar telescope. The Association of Universities for Research in Astronomy operates the Dunn as part of the National Solar Observatory under a cooperative agreement with the NSF.

This ultrasharp image of sunspot AR 10805 shows several objects of current scientific interest. G-band bright points, which indicate the presence of small-scale magnetic flux tubes, are seen near the sunspot and between several granules (columns of hot gas circulating upward).

The dark cores of penumbral fibrils and bright penumbral grains are seen as well in the sunspot penumbra (the fluted structures radiating outward from the spot). These features hold the key to understanding the magnetic structure of sunspots and can only be seen in ultra high-resolution images such as this one. Magnetism in solar activity is the "dark energy problem" being tackled in solar physics today.

Normally such features are beyond the grasp of ground-based solar telescopes because of blurring by Earth's turbulent atmosphere. The Dunn's AO76 system compensates for much of that blurring by reshaping a deformable mirror 130 times a second to match changes in the atmosphere and refocuses incoming light. This allows the Dunn to operate at its diffraction limit (theoretical best) of 0.14 arc-second resolution, rather than the 1.0 to 0.5 arc-second resolution normally allowed by Earth's atmosphere.

The Dunn has two high-order adaptive optics benches, the only telescope in the world with two systems, which enhances instrument setup and operations.

This image was built from a series of 80 images, each 1/100th of a second long (10 ms), taken over a period of 3 seconds by a high-resolution Dalsa 4M30 CCD camera in its first observing run after being added to the Dunn. Speckle imaging reconstruction then compiles the 80 images and greatly reduces residual seeing aberrations.

The camera is part of the equipment suite for the Dunn's Diffraction-Limited Spectropolarimeter, which is designed to analyze magnetic field strength and direction inside sunspots.

The Dunn and its new systems are available for the world solar physics community to use.