According to NASA the 11-day mission will include five spacewalks during which astronauts will install two new instruments, repair two inactive ones and perform some component replacements. The mission is the final one to service the Hubble telescope and is expected to keep the telescope working until 2013 when the orbiting observatory will be replaced by the more powerful James Webb Space Telescope (JWST).
There are serious inherent risks in the Hubble repair mission.
First of all, there’s the ever-increasing amount of space junk in proximity to Hubble. Space shuttle Atlantis and its crew of seven will face increased danger from space junk because of Hubble's extremely high and littered orbit 350 miles up. Even innocuous things like nuts or bolts traveling at 18000 miles per hour could puncture space suits.They will need someone to come and get the cry-- fast -- if their ship sustains serious Columbia-type damage during launch or later in flight. They will not have the luxury of camping out at the international space station while awaiting rescue. The space station will be in another orbit and impossible to reach.
The current mission, once canceled because it was considered too perilous, does have an unprecedented safety net: another space shuttle on the launch pad. There is no guarantee, though, that NASA could pull off a rescue in time to save the Hubble crew. It would take three to seven days, at least, to launch a second shuttle.
Another danger is there will be no ability to check Atlantis to examine it for missing heat shield tiles from the distant ISS, the downfall of Columbia. A piece of insulating foam came off Columbia's external fuel tank during lift-off in January 2003, leaving a hole in the left wing. The shuttle disintegrated during re-entry over Texas on 1 February 2003, killing all seven of its crew.
Should a rescue mission be necessary, similar risks to the rescue shuttle vis-à-vis damaged tiles could result in the unthinkable.
Finally, the repair mission to Hubble will require everything to go just right.
"Hubble servicing missions can be compared to delicate dental work," said HST deputy program manager Mike Weiss of Goddard. "While the dentist fills your tooth or fits you for a crown, his assistant is at the ready handing him, or her, the right tools. Without an assistant the task would take much longer and the chance for errors would increase."
The HST team has spent months developing procedures and tools necessary for this last Shuttle servicing mission to Hubble. In the process they have successfully overcome many obstacles such as safely gaining access to failed circuit boards inside ACS, figuring out a way to pull out boards while wearing pressurized gloves, and installing a new cover on ACS once repairs are complete.
Is this mission worth the risks? Most everyone at NASA thinks so. I don’t.
Why? Just three days later, on May 14th, the European Space Agency will launch two even more advanced telescopes, named Herschel and Planck. Herschel will have the largest mirror ever put in space, 11.5 feet across, half again as big as Hubble's mirror. Planck will have the sharpest vision, detecting differences as small as two parts in a million.
Herschel, will sweep the entire sky every six months over a three-year period. It will build the most accurate map ever made of the cosmos. ''Planck will provide the deepest, clearest, sharpest and least obstructed view of the beginning of the universe ever seen,'' says Benjamin Wandelt, a Planck scientist at the University of Illinois at Urbana-Champaign. It will be ''a quantum leap in our ability to address fundamental questions about how the universe began.''
Then there is the planned JWST telescope. The James Webb Space Telescope will be a large infrared telescope with a 6.5-meter primary mirror. Launch is planned for 2014.
JWST will be the premier observatory of the next decade, serving thousands of astronomers worldwide. It will study every phase in the history of our Universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets like Earth, to the evolution of our own Solar System.
The cost of this last mission to repair Hubble is projected to be $1.1 billion. Let’s not forget the potential 14 lives that will be put at risk.
Finally, According to NASA, Hubble has provided major scientific breakthroughs… Does it need to do more?
• The Hubble Space Telescope has confirmed that the universe is 13.7 billion years old.
• The HST has opened speculation that nearly all galaxies may harbor supermassive black holes.
• The HST has helped scientists determine the process of how planets are born.
• The HST detected the first organic molecule discovered on a planet outside our solar system.
• The HST detected a distant supernova that suggests the universe only recently began speeding up.
• The images of planets, galaxies, nebulae, novae, and, especially, the Ultra Deep Field below have changed forever how mankind can see the known universe. The Ultra Deep Field is an image of a small region of space in the constellation Fornax, made from data accumulated over a period from September 24, 2003 through January 16, 2004. It is the deepest image of the universe ever taken in visible light, looking back approximately 13 billion years, or a little over half a billion years after the universe was created.
I think Hubble has done its service to mankind.
However, President Spock would probably approve, since money flows from Washington like water over Niagara.
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