Mar 26 2010
From The Space Library
RELEASE: 10-277
NASA SEEKS MORE PROPOSALS ON COMMERCIAL CREW DEVELOPMENT
WASHINGTON -- NASA has issued an announcement seeking proposals from U. S. industry to further advance commercial crew space transportation concepts and mature the design and development of system elements, such as launch vehicles and spacecraft. Awards will result in funded Space Act Agreements. Multiple awards are expected to be announced by March 2011 for terms of up to 14 months. Approximately $200 million total is expected to be available for awards under this announcement, but funding is dependent on the 2011 fiscal year appropriations from Congress. The deadline for submitting proposals is Dec. 13. The agreements are expected to generate significant progress toward maturing the design and development of commercial crew systems elements that also ensure crew and passenger safety. The overall objective is to accelerate the availability of U.S. commercial crew transportation capabilities and reduce the gap in U.S. human spaceflight capability. Through this activity, NASA also may be able to spur economic growth as potential new space markets are created. Once developed, crew transportation capabilities could become available to commercial and government customers.
-end-
MEDIA ADVISORY: M10-062
NASA OFFERS LIVE INTERVIEWS WITH HUBBLE EXPERTS FOR 20TH ANNIVERSARY
WASHINGTON -- On the eve of the Hubble Space Telescope's 20th anniversary, NASA will offer live satellite interviews with two of the telescope's premier scientists: Ed Weiler, associate administrator of the Science Mission Directorate at NASA Headquarters in Washington, and former astronaut John Grunsfeld. Interviews are available from 6 to 9 a.m. EDT on Friday, April 23. To participate, reporters should contact Al Feinberg at 202-358-1058 by noon on Thursday. Weiler has worked on the Hubble project since the mid-1970s, while Grunsfeld, who is now deputy director of the Space Telescope Science Institute in Baltimore, participated in three spaceflights to service the observatory. Hubble was launched April 24, 1990, as the world's first space-based optical telescope. Weiler and Grunsfeld will discuss the challenges and successes during its two decades in orbit. Hubble's observations have provided the deepest views of the cosmos ever and captured the minds and imaginations of people around the world. Friday's interviews will be conducted on the NASA TV Live Interactive Media Outlet Channel and carried live on the NASA TV Public and Media Channels. For NASA TV coordinates and downlink information, visit: http://www.nasa.gov/ntv
-end-
RELEASE: 10-243
HUBBLE ASTRONOMERS UNCOVER AN OVERHEATED EARLY UNIVERSE
WASHINGTON -- During a period of universal warming 11 billion years ago, quasars -- the brilliant core of active galaxies -- produced fierce radiation blasts that stunted the growth of some dwarf galaxies for approximately 500 million years. This important conclusion comes from a team of astronomers that used the new capabilities of NASA's Hubble Space Telescope to probe the invisible, remote universe. The team's results will be published in the October 10 issue of The Astrophysical Journal. Using Hubble's Cosmic Origins Spectrograph (COS), the astronomers identified this era, from 11.7 to 11.3 billion years ago, when the ultraviolet light emitted by active galaxies stripped electrons off helium atoms. The process, known as ionization, heated the intergalactic helium from 18,000 degrees Fahrenheit to nearly 40,000 degrees. This inhibited the gas from gravitationally collapsing to form new generations of stars in some small galaxies. Because of its greatly improved sensitivity and lower background "noise compared to previous spectrographs in space, the COS observations were ground-breaking. The observations allowed scientists to produce more detailed measurements of the intergalactic helium than previously possible. "These COS results yield new insight into an important phase in the history of our universe, said Hubble Program Scientist Eric Smith at NASA Headquarters in Washington. Michael Shull of the University of Colorado in Boulder and his team studied the spectrum of ultraviolet light produced by a quasar and found signs of ionized helium. This beacon, like a headlight shining through fog, travels through interspersed clouds of otherwise invisible gas and allows for a core sample of the gas clouds. The universe went through an initial heat wave more than 13 billion years ago when energy from early massive stars ionized cold interstellar hydrogen from the big bang. This epoch is called reionization, because the hydrogen nuclei originally were in an ionized state shortly after the big bang. The Hubble team found it would take another two billion years before the universe produced sources of ultraviolet radiation with enough energy to reionize the primordial helium that also was cooked up in the big bang. This radiation didn't come from stars, but rather from super massive black holes. The black holes furiously converted some of the gravitational energy of this mass to powerful ultraviolet radiation that blazed out of these active galaxies. The helium's reionization occurred at a transitional time in the universe's history when galaxies collided to ignite quasars. After the helium was reionized, intergalactic gas again cooled down and dwarf galaxies could resume normal assembly. "I imagine quite a few more dwarf galaxies may have formed if helium reionization had not taken place, Shull said. So far, Shull and his team only have one perspective to measure the helium transition to its ionized state. However, the COS science team plans to use Hubble to look in other directions to determine if helium reionization uniformly took place across the universe. For illustrations and more information about these results, visit: http://hubblesite.org/news/2010/31 and http://www.nasa.gov/hubble
-end-
'
'
'
'
'
'
