The Hubble Space Telescope almost ready to take action

NASA's famous Hubble Space Telescope seems to have come out of a crush that took the observatory out of service more than two weeks ago.

On October 5, Hubble went into "safe mode" protection after one of its orientation-maintaining gyroscopes failed. The members of the mission team tried to recruit a backup gyro, but this instrument refused to behave and gave abnormal results.

However, a number of troubleshooting activities conducted over the past week seem to have brought the embarrassed gyro to lag behind, NASA officials said today (Oct. 22). The mission team just needs to do some extra testing to make sure everything is fixed. [The Hubble Space Telescope: A 25th Anniversary Photo Celebration]

"The Hubble Operations team plans to perform a series of tests to evaluate the gyroscope's performance under conditions similar to those encountered during routine scientific observations, particularly to move on targets. , lock on a target and perform accurate pointing, "wrote NASA officials. an update of Hubble. "Once these engineering tests are completed, Hubble should soon resume normal scientific activities."

Hubble has six gyroscopes in total, all replaced by astronauts navigating in space during a maintenance mission in May 2009. Each gyroscope is comprised of a wheel that rotates to a constant speed of 19,200 rpm, enclosed in a sealed cylinder. This cylinder floats in a thick fluid (and in fact calls it a float).

"These gyroscopes have two modes – high and low," NASA officials said in the same release. "High mode is a coarse mode used to measure high rotational speeds as the spacecraft rotates in the sky from one target to the next.Low mode is a precision mode used to measure finer rotations when the spacecraft is locked on a target and must remain very stable.

To operate at maximum efficiency, the telescope needs three operational gyroscopes, but it can manage with one if necessary, said NASA officials.

With the October 5 failure, three of Hubble's gyroscopes are now out of service. The emergency gyroscope that the mission team members were trying to put on line had been off for more than 7.5 years. Thus, the rust that appeared at the start on October 6, namely to report abnormally high turnover rates, may not be surprising.

Hubble managers restarted the backup gyroscope on October 16, but that did not do any good. Then, two days later, they ordered the telescope to turn several times in opposite directions to remove blockages that could lead to odd readings of the gyroscope.

And that seems to have done the business.

"After the October 18 maneuvers, the team found a significant reduction in high rates, allowing low-rate rates to be measured for short periods of time," NASA officials said. "On Oct. 19, the operations team asked Hubble to perform additional maneuvers and gyro mode switches, which seems to have solved the problem." The gyro rates now look normal in high and low. low."

Hubble, a joint mission of NASA and the European Space Agency, was launched into Earth orbit aboard Space Shuttle Discovery in April 1990. Astronauts exploring the space have maintained and improved the telescope at many times. They carried out five maintenance missions between December 1993 and May 2009.

Mike Wall's book on the search for extraterrestrial life, "Over there" will be published on November 13 by Grand Central Publishing. Follow him on Twitter @michaeldwall. follow us @Spacedotcom or Facebook. Originally published on Space.com.