CAPE CANAVERAL, Florida (Reuters) - Space shuttle astronauts return this week to outfit the orbiting Hubble Space Telescope for its final — and perhaps greatest — series of observations that edge close to the beginning of time.
The launch of shuttle Atlantis and its seven-member crew is scheduled for 2:01 p.m. EDT on Monday from NASA’s Kennedy Space Center in Florida.
After each of NASA’s four previous servicing missions, the telescope — orbiting 350 miles above Earth — broke new ground in astronomy.
Though its light-collecting mirror is modest by terrestrial telescope standards — just 94 inches in diameter — its precision focus and perch above Earth’s distorting atmosphere make Hubble’s observations the benchmark by which all other observatories are measured.
“There’s no area of modern astronomical research that hasn’t been profoundly affected and changed by Hubble,” said David Leckrone, NASA’s senior project scientist for Hubble. “We have literally rewritten the astronomy textbooks.”
Take for example, the mystery of how galaxies formed. Physicists figured the universe needed time to cool after its explosive birth 13.7 billion years ago to begin making them.
But when astronomers pointed Hubble at what looked like an empty sliver of sky, they got a huge surprise. In place of the baby structures they expected to see were well-formed galaxies.
“The universe got its act together much, much, much earlier than any physicist thought it could,” said Ed Weiler, NASA’s associate administrator for space science.
Hubble, which was launched in 1990, was not always associated with excellence.
It was late, severely over-budget and, worst of all, flawed due to a manufacturing error that left its prime mirror a couple of microns too flat. That may not sound like much — about 1/50th the diameter of a human hair — but for a telescope designed to be able to pick out a dime from 200 miles away it was disaster.
Hubble’s first images of the universe were a blurry, $1.6-billion disappointment.
NASA resurrected the telescope during its first servicing mission in 1993 with corrective optics. Repairs and upgrades followed about every three years.
It has been seven years since NASA’s last trip to Hubble, a delay triggered by safety questions after the 2003 Columbia accident. The mission was once canceled as too risky.
It was reinstated after NASA came up with a plan to rescue the crew in case the shuttle sustained Columbia-like damage during launch. Atlantis will be too far to reach the International Space Station for shelter.
A second shuttle is at the launch pad, ready to fly in case the Hubble team needs a ride home.
Preparing for two shuttle flights is a huge commitment considering that the shuttles are to be retired in 17 months.
And there’s the $10 billion the agency has spent on Hubble so far, plus the millions more yet to come to keep it operating for at least another five years.
The upgrades include a new wide-field camera that should open a window for light streaming from objects formed when the universe was just 500 million years old. NASA hopes to keep Hubble operating at least until 2014 when its successor, the James Webb Space Telescope, can pick up the hunt from there.
“Everything we’ve done up to this point has been preparation for these final five years where Hubble is at the peak of capability,” Leckrone said.
NASA is counting on five spacewalks by the Atlantis crew to install new instruments and make repairs.
“This will be the most challenging servicing mission that’s been faced by our astronauts in terms of the total amount of work,” mission manager Preston Burch said.
Editing by Jim Loney, Editing by Sandra Maler