Hubble telescope hit by mechanical failure

The Hubble Space Telescope uses only essential functions after losing one of the three gyroscopes needed to direct the probe.

The observatory, described as one of the most important scientific instruments ever created, was placed in "safe mode" over the weekend, while scientists were trying to solve the problem.

Hubble was working with four of his six gyroscopes when another failed on Friday.

The telescope was launched in 1990.

What can they do to repair Hubble?

Operators will now try to revive a gyroscope that malfunctioned when the flight controllers tried to put it online to replace the failed gyroscope.

At any given moment, Hubble needs three of its gyroscopes to achieve maximum efficiency.

If it turns out that the gyro "behaves badly" does not work, the observatory in orbit may have to operate on it. This would keep the remaining gyroscopes as long as possible, but somewhat limit the telescope.

Dr. Rachel Osten, Hubble Space Telescope Assistant Chief of Mission, tweeted: "Very stressful weekend, for now HST is in secure mode while we find what to do, another gyroscope has failed. try to bring back the last gyroscope, which had been turned off, and is problematic. "

On the question of switching to a gyroscope, she added: "The plan has always been to go into gyroscopic mode at 1, there are only two gyroscopes left, there is not much difference between 2 and 1, and the time-saving is considerable, what the astro community desperately wants. "

Professor Nial Tanvir from the University of Leicester in the UK told BBC News: "In principle, with a relatively small impact, you can still watch with a gyroscope. heaven you can watch. " and take a little more time to go from one target to another. "

He explained: "In this sense, it's not a disaster, however, if this indicates that another component of the telescope is dead now, it leads you to believe that time is running out for the duration of overall life … that would be a very good shame. "

What about Hubble's replacement?

The space telescope is highly prized by the astronomical community and the observation time has to be managed with caution because of the high demand.

The James Webb Space Telescope (JWST) is the designated successor to Hubble, but has experienced a series of delays and will only be launched in 2021, at the earliest.

Astronomers have recently explained how to extend Hubble's life so that he can continue to serve the astronomy community.

"In many ways, James Webb will be far superior to Hubble, but not in all respects," said Professor Tanvir.

"There are some things we can not do with Hubble for the foreseeable future, so the world of astronomy is hoping Hubble can continue to do that kind of science even after James Webb is launched."

Gyros were the "Achilles Heel" of Hubble?

Hubble has two types of gyroscope. Three older types and three new gyroscopes that should last five times longer. These more recent ones were installed while the telescope was still maintained by astronauts with the space shuttle.

The older ones had caused many problems over the years; the one who failed on Friday was the last of these original gyros.

However, when one of the most recent gyroscopes was on, it was behaving badly. The mission team members hope that it can be brought back, but this is by no means guaranteed.

Controllers must now decide to use Hubble in two gyroscope mode and if one of them fails to switch to one or, alternatively, run it using a gyroscope, wait for that to fail before activate the last one.

Dr. Osten suggested that the problems with gyroscopes were entirely in line with expectations.

She tweeted, "We knew this would happen." The gyro lasted about six months longer than expected (he has almost unplugged it in the spring.) We'll fix the issues and come back. "

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