STS-125 Will Be Last Shuttle To Not Visit ISS
NASA officials outlined
details Tuesday of a challenging mission to repair and upgrade the
Hubble Space Telescope in 2008.
The Hubble servicing mission, designated STS-125, will equip the
orbiting observatory with far greater capabilities than it ever had
before to explore the nature and history of our universe. Space
Shuttle Atlantis is scheduled to lift off in August with a crew of
seven astronauts and a cargo of equipment, tools and new
instruments on the fifth and final mission to service the venerable
telescope, which orbits 350 miles above the Earth.
The shuttle also will carry an IMAX camera to record the
historic mission, for a film scheduled for release in 2010. The
Hubble repair flight will mark the first time the shuttle won't
dock at the International Space Station, since the ill-fated 2003
flight of the shuttle Columbia... and will also mark the last
shuttle flight that doesn't include a trip to the orbiting
station.
"Hubble is, without exaggeration, a national treasure, and all
of NASA is looking forward to seeing it receive this tune up and
upgrade," said Alan Stern, associate administrator for the Science
Mission Directorate at NASA Headquarters, Washington. "I think
Americans are going to be excited when they see the results of this
exciting shuttle mission flower into new discoveries about the
solar system and the larger universe we live in. And let's face it;
it doesn't get much more exciting than sending a team of astronauts
and sophisticated high-tech instruments to make the Hubble better
than it ever was before."
The 11-day shuttle mission will include five spacewalks. During
those spacewalks, astronauts will install two powerful new science
instruments, a new set of the gyroscopes that help stabilize the
telescope, and batteries and thermal blankets to extend Hubble's
operational life until at least 2013. Also, if all goes well, a
degrading Fine Guidance Sensor unit, one of three aboard Hubble,
will be replaced with a refurbished unit to help maintain the
telescope's ability to point and focus on astronomical objects
throughout the universe.

"As both an astronaut and an astronomer, the opportunity to go
back to Hubble is more than a dream come true," said John
Grunsfeld, who will be the mission's lead spacewalker. "This
mission promises to be quite challenging. NASA has put together the
most experienced Hubble crew ever, with three Hubble veterans. The
crew and mission team are in full throttle training, looking
forward to launch and the hard work of servicing Hubble."
Astronauts will attempt
the first ever on-orbit repair of two existing instruments -- the
Space Telescope Imaging Spectrograph (STIS) and the Advanced Camera
for Surveys (ACS). The ACS was the most-used instrument on the
telescope until its failure last January after five years of
operations. The STIS -- the most sophisticated spectrograph ever on
Hubble -- took detailed pictures of celestial objects and separated
light into its components to diagnose the physical conditions of
galaxies, stars, planets and nebulae.
The new instruments to be installed on the telescope are the
Cosmic Origins Spectrograph, or COS, and the Wide Field Camera 3,
or WFC3. Among its many goals, COS will probe the "cosmic web."
This large-scale structure of the universe has its form determined
by the gravity of dark matter and can be traced by galaxies and
intergalactic gas. COS also will explore how this web has evolved
over billions of years and the role it plays in the formation and
evolution of galaxies. The WFC3 will be Hubble's first
"panchromatic" camera, providing wide field-of-view and remarkably
sharp images over a wide range of colors to supplement other
imaging capabilities aboard the Hubble.
"Our goal for this mission is to leave Hubble at the apex of its
scientific capabilities," said David Leckrone, Hubble senior
project scientist at NASA's Goddard Space Flight Center, Greenbelt,
MD. "Our two new instruments, plus the hoped-for repairs of STIS
and ACS, will give astronomers a full 'tool box' with which to
attack some really profound problems, ranging from the nature of
dark matter and dark energy, to the chemical composition of the
atmospheres of planets around other stars."