Houston Chronicle by Alex Stuckey 10/8/2018
The Hubble Space Telescope — credited with altering humankind's understanding of the solar system and how it formed during its almost three decades orbiting Earth — went dark Friday after a mechanical failure.
Hubble put itself into "safe mode" last week after the failure of one of its six gyroscopes, which keep the telescope pointed accurately for extended periods of time as it sends data back to scientists studying space. And NASA said Monday afternoon that the gyroscope's failure wasn't unexpected, as it "had been exhibiting end-of-life behavior for approximately a year."
Hubble needs just three gyroscopes to be fully operational and Friday's failure would have left the telescope with the necessary three — that is, if it weren't for another that was malfunctioning. NASA said Monday afternoon that Hubble would remain in safe mode while officials investigated this further.
"Science operations with Hubble have been suspended while NASA investigates the anomaly," NASA said in a statement. "An Anomaly Review Board, including experts from the Hubble team and industry familiar with the design and performance of this type of gyro, is being formed to investigate this issue and develop the recovery plan."
The telescope can operate — albeit at a lower function — with two, or even just one, working gyroscope. But the events this weekend have left the astronomy community on edge.
During the era when NASA operated its own space shuttles, astronauts could service the telescope, and did so five times before the shuttle program was shuttered in 2011. Now, NASA has no way to get astronauts to the telescope for repairs.
Astronomers are hopeful that the telescope will not go dark for good before its successor, the James Webb Space Telescope, leaves Earth's atmosphere — but they're still nervous about it.
If that happens, "it is not good," said University of Texas at Austin's Steven Finkelstein, who has conducted scientific work with Hubble and already is in line to do so with Webb.
More:
https://www.houstonchronicle.com/news/nation-world/space/article/NASA-working-to-fix-downed-Hubble-Space-Telescope-13290026.php
