Printer Friendly
The Free Library
22,728,043 articles and books

Repairing Hubble: now a waiting game.

The surgery went smoothly, but will it restore the celebrity patient's eyesight? An anxious public must now wait several weeks before specialists can determine the outcome, but experts are guardedly optimistic. After all, four high-flying astronauts - including a former surgeon repaired the myopic my·o·pi·a  
1. A visual defect in which distant objects appear blurred because their images are focused in front of the retina rather than on it; nearsightedness. Also called short sight.

 Hubble Space Telescope Hubble Space Telescope (HST), the first large optical orbiting observatory. Built from 1978 to 1990 at a cost of $1.5 billion, the HST (named for astronomer E. P. Hubble) was expected to provide the clearest view yet obtained of the universe.  with surprising ease last week during five space walks.

The apparent success of the $674 million Hubble mission may usher in Verb 1. usher in - be a precursor of; "The fall of the Berlin Wall ushered in the post-Cold War period"
inaugurate, introduce

commence, lead off, start, begin - set in motion, cause to start; "The U.S.
 a rosier future for manned space flight as well as buoy NASA's sagging reputation. In a call to the astronauts, President Clinton hailed their efforts as "one of the most spectacular space missions in our history"

"It's extremely difficult to keep from getting excited now," says Hubble scientist David S. Leckrone of NASA's Goddard Space Flight Center The Goddard Space Flight Center (GSFC) is a major NASA space research laboratory established on May 1, 1959 as NASA's first space flight center. GSFC employs approximately 10,000 civil servants and contractors, and is located approximately 6.5 miles northeast of Washington, D.C.  in Greenbelt, Md.

Nonetheless, the repair mission aimed at restoring Hubble's mechanical and optical health during an overhaul in the cargo bay of the space shuttle space shuttle, reusable U.S. space vehicle. Developed by the National Aeronautics and Space Administration (NASA), it consists of a winged orbiter, two solid-rocket boosters, and an external tank.  Endeavour - had its anxious moments. During the first space walk, astronauts found they couldn't completely shut two doors housing the gyroscopes they had just replaced. The gap between the doors could allow light to leak into the telescope and ruin observations. Using a strap to pull the doors closer together, the astronauts managed to shut them just minutes before the end of their walk.

Another cliff-hanger came during the third space walk, on Dec. 7. Story Musgrave Franklin Story Musgrave (born August 19, 1935) is a retired NASA Astronaut. He is now a public speaker and consultant to both Disney's Imagineering group and Applied Minds in California.  and Jeffrey Hoffman had gently slid the old Wide-Field and Planetary Camera (WFPC WFPC Wide-Field Planetary Camera (Hubble Space Telescope)
WFPC Wing Fire Protection Controller
) out of its compartment on Hubble, and Musgrave was about to remove the "lens cap" protecting a key, pristine mirror on the new camera, exposing it to the environment of space for the first time. Removing the cap, says Hubble project scientist Edward J. Weiler, "was delicate; he couldn't touch it, and we were watching it at the control room. And sure enough, just as he reached for it, we lost the [video]." But minutes later, the astronauts radioed that they had removed the cap and installed the camera.

Later that night, as the astronauts clamped new magnetometers onto the old ones at the top of the telescope, the cover of one of the old magnetic detectors came loose. Members of the shuttle crew crafted makeshift covers out of extra insulation. Then, with the blue-white marble of Earth clearly visible behind them, Hoffman and Musgrave attached the covers during the final space walk two days later.

The aftermath of the fourth space walk was like a roller-coaster ride. First, astronauts Kathryn Thornton and Tom Akers deftly installed COSTAR co·star also co-star  
A starring actor or actress given equal status with another or others in a play or film.

tr. & intr.v. co·starred, co·star·ring, co·stars
To act or present as a costar.
, a device that sharpens the blurred light bouncing off Hubble's main mirror. But after they added a coprocessor coprocessor

Additional processor used in some personal computers to perform specialized tasks such as extensive arithmetic calculations or processing of graphical displays.
 to improve the memory of Hubble's flight computer, ground controllers were dismayed to find that the computer intermittently radioed spurious signals. Engineers later that day traced the problem to faulty communications rather than a hardware flaw.

Leckrone notes that several initial tasks, such as calibrating the new gyroscopes and determining whether any of the scientific instruments were jostled out of alignment during the mission, must be completed in the next couple of weeks. Only after that can scientists determine the success of the optical repairs. Next week, ground controllers will begin a two-week process of ridding Hubble of contaminating con·tam·i·nate  
tr.v. con·tam·i·nated, con·tam·i·nat·ing, con·tam·i·nates
1. To make impure or unclean by contact or mixture.

2. To expose to or permeate with radioactivity.

 vapor that might otherwise settle on the new WFPC's electronic detectors once they are cooled.

Engineers will then begin aligning Hubble's secondary mirror to aim light precisely into the camera. Around that time, technicians will also deploy a mechanical arm inside COSTAR that holds corrective mirrors. This should enable Hubble's Faint Object Camera The Faint Object Camera (FOC) was a camera installed on the Hubble Space Telescope until 2002. It was replaced by the Advanced Camera for Surveys.

The camera was built by Dornier GmbH and was funded by the European Space Agency.
 to see more clearly.

After finding the optimum focus for both cameraS, scientists will perform the ultimate test some six weeks from now: They will take several images of crowded star fields and faint galaxies to find out whether the repair mission has paid off with a sharper view of the heavens.
COPYRIGHT 1993 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1993, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

 Reader Opinion




Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:the Hubble Space Telescope
Author:Cowen, R.
Publication:Science News
Date:Dec 18, 1993
Previous Article:Superconductivity possible at 250 kelvins.
Next Article:Electrical clues precede some tremors.

Related Articles
Hubble's repair: a second mission needed?
The big fix: NASA attempts to repair the Hubble Space Telescope.
Astronauts snare Hubble, repair flaws.
Hubble finally gets a heavenly view.
The real meaning of 50 billion galaxies.
Y2K problem looms in Hubble repair.
Hubble Space Telescope: Eye wide open.
People, not robots: panel favors shuttle mission to Hubble.

Terms of use | Copyright © 2014 Farlex, Inc. | Feedback | For webmasters