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After five days of loosening bolts, replacing failed parts and, more than a time or two, using elbow grease to overcome recalcitrant hardware, space shuttle Atlantis’ crew has completely revamped the Hubble Space Telescope.
“Hubble never had it better, it’s never been more capable,” said astronaut Dan Burbank, speaking to the crew from Mission Control in Houston. “It’s just been a marvel watching you guys work.
During 36 hours and 56 minutes in space the four spacewalkers — John Grunsfeld, Andrew Feustel, Mike Massimino and Michael Good — accomplished each and every task on NASA’s wish list for the telescope and so far hasn’t dealt with any space debris, which is a mild risk at Hubble’s 350-mile altitude.
By some measures, scientists say, the upgraded telescope is now 90 times more effective than its original configuration in 1990.
Scientists expect it to see deeper into the universe and possibly unlock the secrets of dark energy, an unknown force that’s accelerating the expansion of the universe.
Hubble now has a new state-of-the-art camera to capture images of the cosmos, a new spectrograph, new batteries, two repaired science instruments and other upgrades that should allow the more robust telescope to function for at least five more years.
As a result of its heightened abilities, demand from astronomers for time to use the telescope is higher than ever. Jon Morse, NASA’s top astrophysicist, said there are now as many as 900 requests for time annually, of which only 200 can be granted.
The telescope’s chief scientists were ecstatic following the conclusion of Monday’s fifth and final spacewalk.
Preston Burch, the Hubble program manager, compared the feeling among Hubble scientists to that of an NFL team that had just won a Super Bowl.
“We’re just so tremendously pleased and excited about the outcome of this mission,” Burch said.
Now Burch and his team will spend the next three or four months testing the new instruments and breaking them in. He said to expect the first publicly released photos from the telescope by early September.
For astronaut John Grunsfeld, who has participated in three servicing missions and made his eighth spacewalk to Hubble on Monday, the final foray into space proved emotional.
“One more handshake to Mr. Hubble from me,” he said at one point. “I’m now off the telescope.”
Later, Grunsfeld described his appreciation for the opportunity to return to Hubble after the mission was originally canceled. Following the Columbia tragedy in 2003 NASA initially considered it too dangerous to fly to the telescope’s altitude.
“On this mission in particular, the only way of finding the limits of the possible is by going beyond them into the impossible,” he said. “On this mission, we tried some things that some people said were impossible. … We’ve achieved that, and we wish Hubble the very best.”
The international space station spread its fourth and final set of solar wings on Friday.
The seven visiting astronauts from the shuttle Discovery unfurled a pair of 115-foot blue and gold solar panels from a $298 million component they bolted to the orbiting laboratory on Thursday.
They finished unfolding the panels at midday, absent the drama that has marked the previous installations of three similar power modules. The fragile panels, fashioned from the plastic electrical insulator Kapton and silicon solar cells, have stuck together, snagged and, in one case, ripped when they were unfolded with remote commands issued by astronauts inside the station or from Mission Control.
“It all looks good. We are fully deployed,” Lee Archambault, Discovery’s commander, radioed Mission Control as the operation came to a close in just over two hours.
NASA had allotted up to five-and-a-half hours for the task and was prepared to send spacewalking astronauts out to troubleshoot problems today.
“We all like the station’s new look,” said a relieved Mission Control communicator. “Great work.”
“It went out without a hitch,” said space station commander Mike Fincke, who is nearing the end of a six-month tour on the outpost. Later, he described his emotions as he watched the operation with his face pressed against a window of the station. “I don’t think it was a sigh of relief, as much as it was a shout of triumph,” he said.
Discovery lifted off with the power module on Sunday and delivered it to the station two days later.
The power system will generate enough electricity to power 42 three-bedroom homes. On the station, the electricity will run the life-support systems for a half-dozen astronauts as well as scientific experiments in the station’s Japanese, European and American labs.
Home to no more than three astronauts since 2000, the facility is poised to grow to six tenants in late May.
Today, astronauts Steve Swanson and Joe Acaba, a former teacher, will undertake the second of the Discovery mission’s spacewalks. They plan to perform maintenance on the station’s oldest solar power component. They also will install a navigation antenna for a Japanese cargo ship that is expected to be launched in September.
A high-speed collision between American and Russian satellites in one of the most congested regions of space was bound to happen and has significantly increased the floating pools of debris above the Earth, experts said Thursday.
“The debris cloud created by this collision is like a shotgun blast,” said David Wright, a senior scientist with the Union of Concerned Scientists’ Global Security Program.
It could take decades for the thousands of new fragments — which pose a greater risk to the International Space Station, the space shuttle and Hubble Space Telescope — to fall back to Earth.
The increased risk, which was being assessed by NASA and other scientific organizations, rivals that of a January 2007 Chinese anti-satellite weapons test and a Russian satellite breakup last March.
There is a small possibility that the new debris could prompt NASA to delay plans for a Feb. 22 launch of seven astronauts aboard the shuttle Discovery, officials said.
At NASA’s Orbital Debris Program Office in Houston, experts worked radar and telescope tracking information from the Pentagon’s Space Surveillance Network to determine the increased risk from Tuesday’s collision.
Initial computer simulations revealed a slightly higher risk to the space station, the 220-mile-high home to two American astronauts and a Russian cosmonaut.
“It looks like from the numbers we are getting the risk is not a significant increase,” said Mark Matney, a NASA orbital debris scientist.
However, the heightened risk could be enough to affect plans to launch the Discovery.
While the space station and the shuttle can maneuver out of harm’s way if the military’s radar tracking systems suggest a close call ahead, the orbital facility is much better shielded to withstand a debris strike.
The shuttle, developed in the 1970s before the risk of man-made debris increased, is not as well shielded.
While in orbit, shuttle astronauts orient their spacecraft to fly tail-forward and upside down to protect the ship’s most vulnerable components — the windshield and the heat shields along the wings’ leading edges.
The U.S. and Russian communications satellites collided at an altitude just below 500 miles, or on the fringes of a belt around the Earth extending to 625 miles high. The region is populated with weather and other Earth observation satellites as well as military spy satellites and some unmanned communications spacecraft.
The region looms just above the Hubble Space Telescope. The 20-year-old observatory, which astronauts plan to visit in May on a refurbishing mission, is also in jeopardy of being postponed because of Tuesday’s collision.
“As we go higher, we get to higher debris density,” Matney said. “I don’t know the final answer, but it will affect the risk to that mission. Mission planners will have to take that into account, but we have a little time before that decision has to be made.”