Daring mission to save Hubble
2006-11-01 06:47
Greenbelt - The Hubble Space Telescope, which opened Earth's eyes to an awe-inspiring universe of star births and colliding galaxies, got a reprieve from the junk pile on Tuesday.
Nasa administrator Michael Griffin announced a daring space shuttle flight to repair and upgrade the 16-year-old telescope in the spring of 2008 - a reversal of the previous Nasa chief, who chose to let the orbiting telescope die because of safety concerns for astronauts after the shuttle Columbia disaster.
The $900m rehab mission, carried out in five astronaut spacewalks from the shuttle Discovery, should permit the telescope to keep taking pictures until 2013, allowing scientists to gaze even deeper into the beginnings of the cosmos.
Without this repair mission, Hubble's batteries and stabilising machines could die near the end of the decade, making useless what has been called "the people's telescope".
Hubble's iconic pictures, such as the towering Eagle Nebula, have touched the public in ways that science normally can't do. That's partly because Hubble went from being a failure just after launch to a roaring success, said Syracuse University science and technology professor Henry Lambright.
"The results of Hubble, the beautiful pictures that we see Hubble produce, the images of the cosmos are gripping to everyone who looks at them," Lambright said. "They transmit the magic of space in a way that words cannot."
In 2004, Nasa head Sean O'Keefe cancelled the fourth Hubble servicing mission because if the shuttle's critical heat shield were harmed during launch, there would be no place for the crew to await rescue. It was such damage to the Columbia that led to the deaths of seven astronauts in 2003 as their flight returned to Earth.
Back-up plans
Nasa now has astronauts inspect their spacecraft while it's in orbit, and they are able to hole up in the International Space Station.
Under the Hubble mission plan, Nasa will have a second shuttle waiting to launch at Kennedy Space Centre in case of an emergency. The astronauts and a damaged shuttle could wait beside Hubble for at least 25 days. Also, Nasa has tested heat shield repair techniques and is confident that they can work, Griffin said.
Those back-up plans and technological improvements convinced Griffin to say "yes" to a Hubble repair flight, something everyone in the space agency wanted to do, he said.
"This is the greatest telescope since Galileo," said a beaming Ed Weiler, who was the Hubble chief scientist from 1979 to 1998 and now is director of the Goddard Space Flight Centre in Greenbelt, which is in charge of Hubble.
In the 13 years since Hubble got a major focusing problem fixed, the telescope has changed the field of astrophysics and what scientists think about the universe, especially about the mysterious dark energy and the expansion of the cosmos.
Hubble's history is almost as rocky as the chaotic time period astronomers hope to observe.
Launched in 1990, it was the butt of jokes at first when it wasn't working properly. Comedian Jay Leno quipped that the Hubble wasn't broken - it was the universe that was out of focus.
"The Hubble has been a roller coaster," Weiler said. "It really has."
On the net:
hubblesite.org
- SAPA