Editorial
An Even Better Hubble
Published: May 24, 2009
The Hubble Space Telescope, already hugely successful, should have even greater powers thanks to new instruments installed and repairs made by astronauts on a servicing mission that ended Sunday.
The trip validates the decision of former NASA chief Michael Griffin. He reinstated the mission after it had been canceled by a previous administrator because it was slightly more risky than most shuttle flights. Without refurbishing, Hubble would have limped along with diminished viewing capability until its gyroscopes or key circuits conked out and left it unable to function.
Hubble is the only major space telescope that is close enough for astronauts to reach and refurbish; it was planned that way largely to give the costly shuttle program something useful to do beyond building the scientifically more dubious international space station.
Making the telescope reachable proved fortunate. After Hubble was launched in 1990, NASA discovered to its horror and chagrin that a misshapen mirror blurred its vision, rendering it largely useless. Shuttle astronauts corrected the vision defect, regularly replaced failing gyroscopes and installed ever more sensitive instruments, allowing Hubble to provide brilliantly sharp images.
Among a host of scientific achievements, Hubble has discovered hundreds of proto-galaxies that emitted light when the universe was forming and helped establish the age and expansion rate of the universe.
Now, with the fifth and possibly last servicing mission, NASA has made Hubble potentially better than ever. Astronauts installed two new instruments, repaired two others, and replaced gyroscopes that keep the telescope pointed in the right direction and batteries that provide power. The only glitches were a repair to a survey camera that was only partially successful and frustrating difficulties loosening a bolt and handrail.
If all works as planned, Hubble should be able to peer even deeper into space and farther back in time than it has before. The telescope, circling some 350 miles above Earth, is expected to perform for at least five more years.
That should be long enough to bridge the gap until its successor, the James Webb Space Telescope, is sent to a perch almost a million miles from Earth — four times as distant as the Moon. That is a much better vantage point for viewing the universe without Earth getting in the way. It will also be far beyond the reach of repair parties, so the manufacturers had better get it right the first time.
An Even Better Hubble
Published: May 24, 2009
The Hubble Space Telescope, already hugely successful, should have even greater powers thanks to new instruments installed and repairs made by astronauts on a servicing mission that ended Sunday.
The trip validates the decision of former NASA chief Michael Griffin. He reinstated the mission after it had been canceled by a previous administrator because it was slightly more risky than most shuttle flights. Without refurbishing, Hubble would have limped along with diminished viewing capability until its gyroscopes or key circuits conked out and left it unable to function.
Hubble is the only major space telescope that is close enough for astronauts to reach and refurbish; it was planned that way largely to give the costly shuttle program something useful to do beyond building the scientifically more dubious international space station.
Making the telescope reachable proved fortunate. After Hubble was launched in 1990, NASA discovered to its horror and chagrin that a misshapen mirror blurred its vision, rendering it largely useless. Shuttle astronauts corrected the vision defect, regularly replaced failing gyroscopes and installed ever more sensitive instruments, allowing Hubble to provide brilliantly sharp images.
Among a host of scientific achievements, Hubble has discovered hundreds of proto-galaxies that emitted light when the universe was forming and helped establish the age and expansion rate of the universe.
Now, with the fifth and possibly last servicing mission, NASA has made Hubble potentially better than ever. Astronauts installed two new instruments, repaired two others, and replaced gyroscopes that keep the telescope pointed in the right direction and batteries that provide power. The only glitches were a repair to a survey camera that was only partially successful and frustrating difficulties loosening a bolt and handrail.
If all works as planned, Hubble should be able to peer even deeper into space and farther back in time than it has before. The telescope, circling some 350 miles above Earth, is expected to perform for at least five more years.
That should be long enough to bridge the gap until its successor, the James Webb Space Telescope, is sent to a perch almost a million miles from Earth — four times as distant as the Moon. That is a much better vantage point for viewing the universe without Earth getting in the way. It will also be far beyond the reach of repair parties, so the manufacturers had better get it right the first time.
posted by Nikhil @ 4:19 PM
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