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Apollo-era transporter
In the predawn hours, the Apollo-era crawler-transporter is driven beneath shuttle Discovery's mobile launch platform at pad 39B in preparation for the rollback to the Vehicle Assembly Building. (2min 37sec QuickTime file)
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Unplugging the shuttle
Workers disconnect a vast number of umbilicals running between launch pad 39B and Discovery's mobile launch platform for the rollback. The cabling route electrical power, data and communications to the shuttle. (2min 32sec file)
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Shuttle rollback
The crawler-transporter begins rolling space shuttle Discovery off launch pad 39B at 6:44 a.m. EDT May 26 for the 4.2-mile trip back to the Vehicle Assembly Building. (7min 28sec file)
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Voyager adventures
This animation shows the Voyager spacecraft heading into the solar system's final frontier and the edge of interstellar space. (1min 24sec file)
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Mike Griffin at KSC
NASA Administrator Mike Griffin and Kennedy Space Center Director Jim Kennedy chat with reporters at the Cape on a wide range of topics. The press event was held during Griffin's tour of the spaceport. (27min 48sec file)
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Delta rocket blasts off
The NOAA-N weather satellite is launched aboard a Boeing Delta 2 rocket from Vandenberg Air Force Base, California.

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NOAA pre-launch
Officials from NASA, NOAA, the Air Force and Boeing hold the pre-launch news conference at Vandenberg Air Force Base to preview the mission of a Delta 2 rocket and the NOAA-N weather satellite. (29min 54sec file)

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Clues to planet formation
UNIVERSITY OF MICHIGAN NEWS RELEASE
Posted: May 28, 2005

The most detailed measurements to date of the dusty disks around young stars confirm a new theory that the region where rocky planets such as Earth form is much farther away from the star than originally thought.

These first definitive measurements of planet-forming zones offer important clues to the initial conditions that give birth to planets. Understanding planet formation is key to understanding Earth's origins, yet this remains a mysterious process, said John Monnier, assistant professor of astronomy at the University of Michigan and lead author on the paper, "The near-infrared size luminosity relations for Herbig Ae/Be disks" in a recent edition of Astrophysical Journal.

Very young stars are surrounded by thick, rotating disks of gas and dust, which are expected to eventually disappear as material is either pulled into the star, is blown from the disk, or collects into larger pieces of debris. This transition marks the leap from star formation to planet formation.

The scientists examined the innermost region of such disks where the star's energy heats the dust to extremely high temperatures. These dusty disks are where the seeds of planets form, where dusty particles stick together and eventually grow to large masses.

However, if the dust orbits too close to the star, it evaporates, shutting off any hope of planet formation. It's important to know where the evaporation begins since it has a dramatic effect on planet formation, Monnier said. The initial temperature and density of dust surrounding young stars are critical ingredients for advanced computer models of planet formation.

For the study, scientists looked at young stars that are about one and a half times the mass of the sun. "We can study these stars more in-depth because they are brighter and easier to see," Monnier said.

In the last decade or so, beliefs about the systems that build planets have changed drastically with the onset of powerful observatories that can take more precise measurements, Monnier said.

They found that measurements thought to be accurate were actually very different than originally thought.

For this work, scientists used the two largest telescopes in the world linked together to form the Keck Interferometer. This ultra-powerful duo acts as the ultimate zoom lens allowing astronomers to peer into planetary nurseries with 10X the detail of the Hubble Space Telescope. By combining the light from the two Keck Telescopes, researchers were able to achieve the capabilities of a single telescope that spans a football field, but for a fraction of the cost, Monnier said.

Other key authors were Rafael Millan-Gabet and Rachel Akeson of the Michelson Science Center. Other key institutions included the Caltech-run, NASA Jet Propulsion Laboratory and the W.M. Keck Observatory in Kamuela, Hawaii.

The Keck Interferometer was funded by NASA and developed and operated by Jet Propulsion Lab, W.M. Keck Observatory, and the Michelson Science Center.