May 11, 2009

Atlantis Reaches Orbit In Mission To Repair Hubble

NASA's space shuttle Atlantis launched on Monday with plans to make critical repairs to the Hubble space telescope.

Shuttle Atlantis launched from Kennedy Space Center in Florida at 1401 EDT, carrying seven crewmembers that will take part in the fifth and final flight to repair Hubble. NASA's space shuttle program is expected to come to an end in 2010.

Crewmembers arrived at the launch pad on Sunday as NASA told reporters that the weather provided a 90 percent chance of a successful launch on Monday. The team includes commander Scott Altman, pilot Greg Johnson, flight engineer Megan McArthur, lead spacewalker John Grunsfeld, and astronauts Michael Massimino, Michael Good and Andrew Feustel.

"Our workload is going to be very high," Grunsfeld told BBC News on Sunday.

"It's going to be a marathon at a sprint pace for 11 days on orbit."

Atlantis is the first mission planned since the Columbia disaster in 2003. The incident caused NASA to delay critical upgrade missions to Hubble, which has been crippled by camera issues, and instrument failures. The telescope's computer has also gone offline.

Since the Columbia incident, NASA has made changes that include developing the International Space Station as an emergency shelter for astronauts in case the shuttle sustains damages during liftoff.

However, Atlantis' intended mission will take it far out of reach of the ISS, so NASA has put together a second shuttle that would be launched in the case of an emergency.

"On this mission, we're going for broke," Hubble project scientist David Leckrone told Reuters. "We set the bar extraordinarily high for ourselves."

Over the course of five spacewalks, Atlantis crewmembers will install two new instruments, repair two inactive ones and perform the component replacements that will keep the telescope functioning into at least 2014.

NASA will install the so-called Cosmic Origins Spectrograph, which will observe the light put out by extremely faint, far-away quasars and see how that light changes as it passes through the intervening gas between distant galaxies.

"It's an important player in the story of how galaxies are formed and how the chemical makeup of the universe has changed over time," Leckrone said.

The mission will also see the installation of the new Wide Field Camera 3, which will equip Hubble to take massive, detailed pictures over a wide array of colors.

"If I want a complete family album of the universe, I need to look at it in all these different wavelengths," Leckrone said. "This will be the first time we've had an opportunity to take all these different images together, to have a comparable quality of pictures across this whole wavelength band."

The crew is expected to replace only the pieces within the instruments that have failed rather than the instruments themselves.

"But those instruments were never designed to be repaired in space. In fact, they were specifically designed not to come apart," said NASA."

"When we first looked at it, we were going "Ëœwell, maybe, maybe not,'" Ceccacci said.

But the team has put together a plan that they believe will work, although it will not be easy. For example, Ceccacci said the spectrograph's repair will require the spacewalkers to remove more than 100 screws to access a computer card they will pull out and replace.

"If (the mission) is successful, as we all hope, it will not just return Hubble to health but increase its capability tremendously with the addition of two new, even more powerful instruments," Martin Barstow, professor of astrophysics and space science at the University of Leicester, UK, told BBC News.

"It is a testament to the ingenuity and commitment of many scientists and engineers. I have no doubt that we will continue to be amazed by Hubble's new discoveries during the next few years."

Hubble was launched by shuttle Discovery in 1990, where it was put into an orbit of 304 nautical miles above the Earth.

"Since then it's circled Earth more than 97,000 times and provided more than 4,000 astronomers access to the stars not possible from inside Earth's atmosphere," said NASA. "Hubble has helped answer some of science's key questions and provided images that have awed and inspired the world."

"We've actually seen an object that emitted its light about 13 billion years ago," said  Leckrone. "Since the universe is 13.7 billion years old, that's its infancy, the nursery. From the nearest parts of our solar system to further back in time than anyone has ever looked before, we've taken ordinary citizens on a voyage through the universe."

Lead Flight Director Tony Ceccacci referred to the installation to be conducted over the series of spacewalks as a process "more like brain surgery than construction."

"On station spacewalks, you're installing large pieces of equipment "“ trusses, modules, etc. "“ and putting it together like an erector set. You can't do that with Hubble. Hubble spacewalks are comparable to standing at an operating table, doing very dexterous work," said Ceccacci.

"I think [this] is motivating us because we know there's nobody coming after us to do anything we don't get done," said Commander Altman.

"This is it. We either get it done or it doesn't happen."


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