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Andromeda adrift in sea of dust in new Spitzer image NASA/JPL NEWS RELEASE Posted: June 5, 2006
"What's really interesting about this view is the contrast between the galaxy's smooth, flat disk of old stars and its bumpy waves of dust heated by young stars," said Dr. Pauline Barmby of the Harvard-Smithsonian Center for Astrophysics, Cambridge, Mass. Barmby and her colleagues recently observed Andromeda using Spitzer. Barmby and her team used the Spitzer data to make drastically improved measurements of Andromeda's infrared brightness. They found that the galaxy shines with the same amount of energy as about 4 billion suns. Based on these measurements, the astronomers confirmed that there are roughly one trillion stars in the galaxy. Our Milky Way galaxy is estimated to house a couple hundred billion stars. "This is the first time the stellar population of Andromeda has been determined using the galaxy's infrared brightness," said Barmby. "It's reassuring to know our numbers are in agreement with previous estimates of the mass of the stars based on the stars' motion." The new false-colored portrait also provides astronomers with the best look yet at the dust-drenched spiral arms that swirl out of the galaxy's center, a region hidden by bright starlight in visible-light images. Dust and gas are the building materials of stars. They are clumped together throughout the spiral arms, where new stars are forming. "The Spitzer data trace with startling clarity the star-forming material all the way into the inner part of the galaxy," said Dr. George Helou, deputy director of NASA's Spitzer Science Center at the California Institute of Technology in Pasadena. "The challenge is to understand what shapes the distribution of this gas and dust, and what modulates the star formation at different locations." Spitzer's infrared array camera captured infrared light emanating from both older stars (blue) and dust made up of molecules called polycyclic aromatic hydrocarbons (red). These carbon-containing molecules are warmed by sunlight and glow at infrared wavelengths. They are often associated with dense clouds of new stars, and can be found on Earth in barbecue pits and car exhaust, among other places. The Andromeda galaxy, also known by astronomers as Messier 31, is located 2.5 million light-years away in the constellation Andromeda. It is the closest major galaxy to the Milky Way, making it the ideal specimen for carefully examining the nature of galaxies. On a clear, dark night, the galaxy can be spotted with the naked eye as a fuzzy blob. Andromeda spans about 260,000 light-years, which means that a light beam would take 260,000 years to travel from one end of the galaxy to the other. By comparison, the Milky Way is about 100,000 light-years across. When viewed from Earth, Andromeda occupies a portion of the sky equivalent to seven full moons. Spitzer's wide field of view allowed the telescope to capture a complete snapshot of the Andromeda galaxy, though the task wasn't easy. The final mosaic consists of 3,000 or so individual picture frames stitched together seamlessly. Barmby presented these observations today at the 208th meeting of the American Astronomical Society in Calgary, Canada. Other members of Barmby's team include: Drs. Steven Willner, Matthew Ashby, John Huchra and Michael Pahre of the Harvard-Smithsonian Center for Astrophysics; Drs. Luciana Bianchi and David Thilker of The Johns Hopkins University, Baltimore, Md.; Drs. Charles Engelbracht, Karl Gordon, Joannah Hinz, Pablo Perez-Gonzalez and George Rieke of the University of Arizona, Tucson; and Drs. Robert Gehrz, Roberta Humphreys, Elisha Polomski and Charles Woodward of the University of Minnesota, Twin Cities. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center. Spitzer's infrared array camera was built by NASA's Goddard Space Flight Center, Greenbelt, Md. The instrument's principal investigator is Giovanni Fazio of the Harvard-Smithsonian Center for Astrophysics. |
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Space shuttle program manager Wayne Hale and launch director Mike Leinbach hold this news conference May 31 from Kennedy Space Center to offer a status report on STS-121 mission preparations. The briefing was held at the conclusion of the debris verification review, which examined the external fuel tank and threats to the shuttle from impacts during launch.
Dial-up: 
NASA created its Tracking and Data Relay Satellite (TDRS) system to serve as a constellation of orbiting spacecraft that would replace the costly ground tracking stations scattered around the globe for communications with space shuttles and other satellites. Space shuttle Discovery's STS-29 mission in March 1989 launched the massive TDRS-D craft. This post-flight film narrated by the crew shows the deployment, the astronauts running a series of medical tests and the monitoring of a student-developed chicken embryo experiment.
Space shuttle Columbia began mission STS-61C with a beautiful sunrise launch in January 1986 after several delays. Led by commander Hoot Gibson, the astronauts deployed a commercial communications satellite and tended to numerous experiments with the Materials Science Laboratory, Hitchhiker platform and Getaway Special Canisters in the payload bay. The crew included Congressman Bill Nelson of Florida, the first U.S. Representative to fly in space. Watch this post-flight film narrated by the astronauts.
The Boeing Delta 4 rocket launches from pad 37B at Cape Canaveral Air Force Station with the GOES-N spacecraft, beginning a new era in weather observing for the Americas.
As night fell over Kennedy Space Center on May 19, space shuttle Discovery reached launch pad 39B to complete the slow journey from the Vehicle Assembly Building. Discovery will be traveling much faster in a few weeks when it blasts off to the International Space Station.
The November 1985 flight of space shuttle Atlantis began with a rare nighttime blastoff. The seven-member crew, including a Mexican payload specialist, spent a week in orbit deploying three communications satellites for Australia, Mexico and the U.S. And a pair of high-visibility spacewalks were performed to demonstrate techniques for building large structures in space. The crew narrates the highlights of STS-61B in this post-flight crew film presentation.
Eight astronauts, the largest crew in history, spent a week in space during the fall of 1985 aboard shuttle Challenger for mission STS-61A, the first flight dedicated to the German Spacelab. The crew worked in the Spacelab D-1 laboratory conducting a range of experiments, including a quick-moving sled that traveled along tracks in the module. A small satellite was ejected from a canister in the payload bay as well. The astronauts narrate the highlights of the mission in this post-flight film.