NASA officials announced today that the upcoming mission for
repairing the Hubble telescope would be delayed for four or five weeks.
Earlier this year, NASA said it would send a special shuttle
mission in August 2008 to spruce up the Hubble on a long overdue servicing
mission. The U.S.
astronauts selected for the next servicing mission to the Hubble Space
Telescope had begun already their training in February last year. But now the
mission was delayed to late September or early October.
"Right now Hubble's mission is scheduled for August 28;
we really cannot make that date with the external tank processing,"
shuttle program manager John Shannon explained at a press conference Thursday.
"The changes we have made add about four to five weeks
of processing time on those two tanks," he said. The external fuel tanks
were redesigned from scratch after the Columbia
disaster.
Shuttle program manager John Shannon said it's taken more
time to incorporate all the design changes to the than had been expected.
"It's a small price to pay to tell you the truth, four
to five weeks, for all the improvements that we're getting on this tank," Shannon added.
The new tank delayed also Discovery's flight to the
international space station from April until May 31.
NASA had intended to mothball the Hubble before the new
telescope was in place, a decision that was met with protests among astronomers
who have been able to look into space 2.2 billion light years and more because
they don't have to peer through Earth's atmosphere.
Missions to the space station are easier because ISS crew is
on hand to help inspect the shuttle. The ISS also offers up to three months
refuge for visiting crew in case of an emergency. The Hubble, which orbits 580
kilometers above Earth, offers neither. That means the shuttle would have to
survive on its own for up to 25 days, with the second shuttle on stand-by at a
separate launch pad for a rescue mission.
A year ago, the Hubble telescope's most far-seeing camera
shut down due to a possible power failure and other problems, prompting NASA
engineers to put the entire telescope on temporary standby. The Advanced Camera
for Surveys (ACS) was installed in 2002 in a special shuttle mission to replace
the old space camera - in orbit since 1990 - and was hailed as the gateway to
some of humankind's most spectacular views of the universe.
The STS-125 mission aims to install a cosmic origins
spectrograph and to replace a wide field camera in operation since 1993 with a
Wide Field Camera 3. This latest camera will be the first on the Hubble that
can cover everything from the ultraviolet to the infrared spectrum.
The aging telescope is also in need of new batteries, new
gyroscopes and a new thermal blanket to insulate it from the severe temperature
swings as it orbits Earth every 45 minutes. Also scheduled for fixing is the Advanced
Camera for Surveys.
Theoretically, the James Webb observatory will replace
Hubble in 2013 the earliest. The Hubble Space Telescope (HST) was first
conceived in 1946 by astronomer Lyman Spitzer, constructed since 1979 and
launched in 1990.
