Hubble ready for final service

NASA will on Monday launch the shuttle Atlantis and seven astronauts into orbit on a high-risk last service mission to one of the greatest scientific instruments ever, the space telescope Hubble.

There is no room for error, the US space agency warned this week, in the fifth and final maintenance operation on the Hubble before the shuttle fleet is retired.

If all goes well, NASA says the telescope's long-overdue service will extend the star-gazer's life by at least five years.

"If successful we will be entering our second quarter century. That's not bad for a mission that we hoped will last for 10 to 15 years," said Ed Weiler, associate administrator of NASA'S science missions directorate.

Hubble "will be more powerful and robust than ever before and will continue to enable world class science for at least another five years an overlap with the James Webb Space Telescope" its successor, he added.

Launched in 1990, Hubble has long been considered the greatest tool in the history of astronomy.

Using powerful instruments to peer into deep space, it has provided profound insights into the origins and evolution of the universe.

A journey to the 11-ton Hubble carries more risk of being hit by space debris or micrometeorites than a flight to the International Space Station, as the telescope orbits at almost twice the height of the ISS.

But officials hope the nearly 11-day mission will allow Hubble to keep functioning until 2014, when it is due to be replaced by the James Webb Space Telescope, a highly sophisticated space telescope with an eagle-eye camera.

The mission launch is scheduled for 1801 GMT Monday from the Kennedy Space Centre near Cape Canaveral, Florida.

But even before undertaking the challenging task of carrying out a maintenance job 575 kilometres above Earth, NASA has left itself only a limited window for a launch.

The shuttle must liftoff on either May 11, 12 or 13 because planned military launch activities would block all other launches until May 22.

Hubble's servicing will entail five space walks, each lasting up to seven hours. Crew members plan to replace the telescope's six gyroscopes and batteries and upgrade its optical instruments.

The crew will carry out a variety of tasks including replacing electronic circuit boards, said scientist Dave Leckrone.

Astronauts will also install a new imaging camera and a Cosmic Origins Spectrograph -- an especially sensitive instrument designed to split light it captures into individual wavelengths.

The spectrograph, NASA says, will not only be able to study stars, planets and galaxies but also basic elements found throughout the cosmos, such as carbon and iron.

And the new instruments will allow Hubble to peer even further back into time, perhaps as far back as some 600 million years before the Big Bang, much further than the billion years it can reach back now.

The maintenance is overdue after the years-long delay for US space flights since the 2003 Columbia disaster that saw the shuttle disintegrate as it re-entered Earth's atmosphere, killing all seven crewmembers.

Last year a flight by the shuttle Atlantis to the telescope had to be twice rescheduled after it had a computer failure on board.

NASA announced this week that the IMAX Corporation and the filmmaking Warner Bros. company will launch IMAX 3-D cameras with the shuttle to document the mission.

Astronauts will use the cameras during the five spacewalks and, along with the telescope's astounding array of images of distant galaxies, the footage will be released next year as the movie "Hubble 3D." AFP link..