Wednesday, April 29, 2015

Hubble Space Telescope’s 25th Anniversary

Even though it is slated to be retired in five years time, is there still life left in the Hubble Space telescope?

By: Ringo Bones

Since its launch into low earth orbit by the Space Shuttle Discovery back in April 24, 1990, the Hubble Space Telescope has proven itself to be the proverbial “little telescope that could”. Freed from the inherent turbulence of the earth’s atmosphere by placing it in orbital space, the Hubble Space Telescope has the potential to be far better than any earthbound telescope that has come before. But for its entire 25-year lifespan is not totally free from controversy.

When it was found out that its primary mirror was misshapen – as in light rays hitting the mirror’s edge is reflected differently in comparison to the light rays hitting the center of the mirror by as much as one-thirteenth the thickness of the human hair which significantly affected its performance when looking at distant galaxies tens of millions of light-years away. The mainstream press dubbed it the 2-billion dollar blunder upon hearing the news and some folks – most of them your right-wing conservative types – are the ones voicing the loudest criticisms of the fledgling space telescope.

For all intents and purposes, Reagan era “conservative” America may have something to do on why the misshapen main mirror of the Hubble Space Telescope was overlooked and was only found out after it was sent into space. Perkin Elmer – the Hubble Space Telescope’s main mirror contractor – wasn’t allowed to verify if they’ve ground the mirror accurate enough using the test jig at the then Lockheed Aircraft Corporation (before they merged with the famed cruise missile manufacturer Martin Marietta). Given that it was still the height of the Cold War, Hubble’s main mirror never got the opportunity for troubleshooting in an optical test jig at Lockheed where they test the main mirrors of NSA’s 1980s era Keyhole Reconnaissance Satellites for fears that the then Soviet Union might know the optical capabilities of the 1980s era U.S. spy satellites – thus the “blunder” that got overlooked. But given that the main mirror was misshapen in such a precise manner, folks at NASA managed to device a “contact lens” to correct the Hubble Space Telescope’s misshapen main mirror – at a fraction of the total cost of the space telescope.

With a Space Shuttle flight to fix the Hubble back in December 2, 1993, a team of NASA astronauts led by Story Musgrave managed to install the “contact lens package” – as in the COSTAR corrective optics module - to fix the Hubble. The mission was totally worth it when in July 16, 1994 the Hubble Space Telescope managed to give humanity a “ringside seat” to the crash of the comet Shoemaker-Levy 9 to the planet Jupiter. Then came the “Hubble Deep Field” series of images and a host of other images that forever changed the science of astronomy.

But the Hubble Space Telescope is truly the “space based telescope that could”. As in the Hubble consumes as much power as a household electric clothes drier and its “jitter spec” is of 0.007 arc-second accuracy – in layman’s terms it is like pointing a hand-held laser pointer on the top of the Washington Monument and keep it steady enough to aim at a dime on top of the Empire State Building while keeping it steady enough to keep the laser point or spot aimed squarely at Roosevelt’s profile on the said dime.  

Since the late 1990s, the Hubble Space Telescope has been slated for replacement. The James Webb Space Telescope which will be placed over a million miles away from earth. If its specs can be trusted, the James Webb Space Telescope has the potential to detect any earth-like planet within 10,000 light-years. And despite its age and scores of upgrades later, it seems that the Hubble Space Telescope’s “imminent” retirement 5 years from now is not yet certain given that it was originally designed to last for only 15 years.

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