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In this April 25, 1990, NASA-supplied photograph, most of the Hubble Space Telescope can be seen suspended in space by Discovery's Remote Manipulator System (RMS) following the deployment of a portion of its solar panels and its antennas. This is one of the first pictures of STS-31 mission published by NASA on April 30th. The Hubble Space Telescope, one of NASA's glories, is celebrating its 25th anniversary on Friday, April 24, 2015. With over a million sightings, including those from the most distant galaxies and the Older never greeted by humanity, no artificial satellite has touched as many minds or hearts as Hubble. (NASA via AP)
NASA's Hubble Space Telescope is still in secure mode as of Monday morning, while engineers are working on diagnosing and repairing a gyro failure that has put out of action the orbital observatory's 25 years old, October 5th.
For the moment, Hubble is not alone in his convalescence. The Chandra X-ray observatory of NASA went into safe mode on October 10, as a result of a computer problem in which a gyroscope sent 3 seconds of bad data to the computer from Chandra. Using the wrong data, the computer calculated an incorrect and seemingly alarming momentum for the telescope. The telescope automatically goes into safe mode, but NASA engineers say they're switching to a backup gyroscope, leaving it in reserve, and downloading flight software patches. Chandra is already well underway and will return to science as usual towards the end of this week, around October 20th.
This is an impressive recovery for the 19-year-old space telescope, which is now well engaged in its mission. The Space Shuttle Columbia, as part of a mission commissioned by Astronaut Eileen Collins, orbited the X-ray observatory in 1999. Chandra became the third of four major observatories of the NASA, alongside Hubble, the Compton Gamma Ray Observatory (which was orbited in 2000). and the Spitzer Space Telescope, which still performs infrared thermal astronomy in low Earth orbit. The name of Chandra means "moon" in Sanskrit and is also a tribute to the astronomer Subrahmanyan Chandrasekhar.
What do you do when the backup fails?
The Hubble gyroscope problem may be less easy to solve, but NASA says the telescope will return to normal scientific operations in one way or another. Hubble relies on its gyroscopes to measure the speed at which the telescope rotates; With data from three gyroscopes, the telescope's on-board computer can control its orientation with incredible accuracy, but it can still work with one or two, albeit with a slightly more limited view of the sky.
When things started to go wrong last week, three of Hubble's six gyroscopes were working together to help steer the telescope and hold it against the target. Two others had already failed and one of them had been turned off, put in reserve in case of failure. Then, one of the three gyroscopes in operation failed.
"The failed gyroscope had end-of-life behavior for about a year and that was not surprising," NASA wrote in a press release on Oct. 8. The engineers triggered the reserve gyroscope, but the latter also failed. – or at least, "the spacecraft telemetry analysis revealed that it did not reach the level required for operations" and, given NASA's high standards, This is a failure.
Specifically, the emergency gyro indicated that the telescope was spinning a lot, much faster than it actually was. "It sounds like a speedometer on your car constantly showing that your speed is 100 miles faster than it actually does, it correctly indicates when your car is accelerating or slowing down, and by how much, but the actual speed is imprecise, "The agency explained in an update of October 12. NASA has put Hubble in safe mode while engineers are working to diagnose the problem and determine what to do. If they find a way to repair the uncooperative gyro – probably with a hotfix – Hubble will return to work with three gyroscopes and no backups. But if the problem can not be solved, Hubble will continue to operate with a gyroscope running and a backup.
In this image provided by NASA / JSC, astronauts Steven L. Smith and John M. Grunsfeld are photographed during an extravehicular activity (EVA) during the Hubble maintenance mission of the STS-103, conducted by Discovery in December 1999. The Hubble Space Telescope, one of NASA's glories, celebrates its 25th anniversary on Friday, April 24, 2015. With over a million sightings, including those from the most distant galaxies and the oldest ever hosted by mankind, no artificial satellite has touched as many minds or hearts as Hubble. (NASA / JSC via AP)
The story of Hubble also concerns the space shuttle
The current set of gyroscopes has been on board since 2009, a departure gift from Hubble's latest shuttle repair mission, which replaces the original set of six gyroscopes. In 2005, in the hope of extending the life of Hubble's equipment and thus extending its mission, NASA went from three gyroscopes to two, two more as a backup. This allowed Hubble to point a little less precisely than three gyroscopes, but still able to make very detailed astronomical observations. But a gyroscope broke down in 2007 and it turned out that the electrical wires of the gyroscope motors were corroded, thanks to the oxygen pressurized air used to pump the thick fluid in which the gyroscopes are suspended. The replacement gyroscopes delivered in 2009 used nitrogen instead of oxygen, and engineers expected that they would last much longer than the first batch.
As Kevin Anderton pointed out, if the space shuttle or its successor was still flying, a crewed mission could potentially carry new gyroscopes to Hubble or repair existing ones. Hubble's designers had the space shuttle in mind when they designed the telescope with relatively easy-to-disassemble instruments designed to be replaced by astronauts on a maintenance mission. A total of five missions have made repairs or upgrades on Hubble from 1993 to 2009, but for the moment, the options are quite limited and there is no real replacement for the Space Shuttle at this time. ;horizon. Boeing's CST-100 Starliner and SpaceX's Crew Dragon are both focused on crew transportation: transporting astronauts to the International Space Station or possibly to others. Until now, their designs do not seem to have the ability to house and support a crew in orbit for several days on a maintenance mission to Hubble, and they do not have the cargo hold or robotic arm of the shuttle. .
The story of Hubble is closely linked to that of the Shuttle program. Shuttle Challenger exploded at its launch in January 1986, taking the life of the entire crew. NASA quickly immobilized the rest of the shuttle fleet while a committee was investigating the tragedy. The planned launch of Hubble in October 1986 was postponed until April 1990. After launch, the $ 1.5 billion telescope would have been an almost complete loss for astronomy if a shuttle mission had not not been able to install corrective optics. And one last mission in 2009, which removed these optics and replaced several Hubble instruments with improved versions, was delayed much like the launch mission, by the catastrophic loss of a space shuttle – this time. Columbia. And now, with the shuttle program completed in part as a result of Columbia's loss, Hubble is on its own 540 km (340 miles) above Terra Firma.
It's nowhere near
Well, not quite alone; It has remote support from engineers on Earth, who are actively working on finding solutions. And NASA engineers do not easily abandon their scientific robots; NASA is still trying to contact Opportunity, making sure that the dust storm on Mars is slowly dissipating. NASA says Hubble will send home detailed images of the cosmos for years to come. But NASA says it will not happen for years. Just last week, astronomers discovered for the first time a moon in orbit around an exoplanet, thanks to the 19-year-old space telescope. And Hubble still has a decade or two, hopefully, so there could be many more discoveries of this type to come.
And if all goes well, it will be joined in 2021 by the James Webb space telescope. Unlike Hubble, Webb was not designed for shuttle maintenance and will run around 1.5 million kilometers at a point in space called Lagrange's second point, so far from Earth that the gravity of the Earth and that of the Sun sway. . This distance would have put James Webb well beyond a space shuttle mission in case of trouble – but James Webb's design still includes a docking ring, just in case.
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In this April 25, 1990, NASA-supplied photograph, most of the Hubble Space Telescope can be seen suspended in space by Discovery's Remote Manipulator System (RMS) following the deployment of a portion of its solar panels and its antennas. This is one of the first pictures of STS-31 mission published by NASA on April 30th. The Hubble Space Telescope, one of NASA's glories, is celebrating its 25th anniversary on Friday, April 24, 2015. With over a million sightings, including those from the most distant galaxies and the Older never greeted by humanity, no artificial satellite has touched as many minds or hearts as Hubble. (NASA via AP)
NASA's Hubble Space Telescope is still in secure mode as of Monday morning, while engineers are working on diagnosing and repairing a gyro failure that has put out of action the orbital observatory's 25 years old, October 5th.
For the moment, Hubble is not alone in his convalescence. The Chandra X-ray observatory of NASA went into safe mode on October 10, as a result of a computer problem in which a gyroscope sent 3 seconds of bad data to the computer from Chandra. Using the wrong data, the computer calculated an incorrect and seemingly alarming momentum for the telescope. The telescope automatically goes into safe mode, but NASA engineers say they're switching to a backup gyroscope, leaving it in reserve, and downloading flight software patches. Chandra is already well underway and will return to science as usual towards the end of this week, around October 20th.
This is an impressive recovery for the 19-year-old space telescope, which is now well engaged in its mission. The Space Shuttle Columbia, as part of a mission commissioned by Astronaut Eileen Collins, orbited the X-ray observatory in 1999. Chandra became the third of four major observatories of the NASA, alongside Hubble, the Compton Gamma Ray Observatory (which was orbited in 2000). and the Spitzer Space Telescope, which still performs infrared thermal astronomy in low Earth orbit. The name of Chandra means "moon" in Sanskrit and is also a tribute to the astronomer Subrahmanyan Chandrasekhar.
What do you do when the backup fails?
The Hubble gyroscope problem may be less easy to solve, but NASA says the telescope will return to normal scientific operations in one way or another. Hubble relies on its gyroscopes to measure the speed at which the telescope rotates; With data from three gyroscopes, the telescope's on-board computer can control its orientation with incredible accuracy, but it can still work with one or two, albeit with a slightly more limited view of the sky.
When things started to go wrong last week, three of Hubble's six gyroscopes were working together to help steer the telescope and hold it against the target. Two others had already failed and one of them had been turned off, put in reserve in case of failure. Then, one of the three gyroscopes in operation failed.
"The failed gyroscope had end-of-life behavior for about a year and that was not surprising," NASA wrote in a press release on Oct. 8. The engineers triggered the reserve gyroscope, but the latter also failed. – or at least, "the spacecraft telemetry analysis revealed that it did not reach the level required for operations" and, given NASA's strict standards, Somehow acts of a failure.
Specifically, the emergency gyro indicated that the telescope was spinning a lot, much faster than it actually was. "It sounds like a speedometer on your car constantly showing that your speed is 100 miles faster than it actually does, it correctly indicates when your car is accelerating or slowing down, and by how much, but the actual speed is imprecise, "The agency explained in an update of October 12. NASA has put Hubble in safe mode while engineers are working to diagnose the problem and determine what to do. If they find a way to repair the uncooperative gyro – probably with a hotfix – Hubble will return to work with three gyroscopes and no backups. But if the problem can not be solved, Hubble will continue to operate with a gyroscope running and a backup.
In this image provided by NASA / JSC, astronauts Steven L. Smith and John M. Grunsfeld are photographed during an extravehicular activity (EVA) during the Hubble maintenance mission of the STS-103, conducted by Discovery in December 1999. The Hubble Space Telescope, one of NASA's glories, celebrates its 25th anniversary on Friday, April 24, 2015. With over a million sightings, including those from the most distant galaxies and the oldest ever hosted by mankind, no artificial satellite has touched as many minds or hearts as Hubble. (NASA / JSC via AP)
The story of Hubble also concerns the space shuttle
The current set of gyroscopes has been on board since 2009, a departure gift from Hubble's latest shuttle repair mission, which replaces the original set of six gyroscopes. In 2005, in the hope of extending the life of Hubble's equipment and thus extending its mission, NASA went from three gyroscopes to two, two more as a backup. This allowed Hubble to point a little less precisely than three gyroscopes, but still able to make very detailed astronomical observations. But a gyroscope broke down in 2007 and it turned out that the electrical wires of the gyroscope motors were corroded, thanks to the oxygen pressurized air used to pump the thick fluid in which the gyroscopes are suspended. The replacement gyroscopes delivered in 2009 used nitrogen instead of oxygen, and engineers expected that they would last much longer than the first batch.
As Kevin Anderton pointed out, if the space shuttle or its successor was still flying, a crewed mission could potentially carry new gyroscopes to Hubble or repair existing ones. Hubble's designers had the space shuttle in mind when they designed the telescope with relatively easy-to-disassemble instruments designed to be replaced by astronauts on a maintenance mission. A total of five missions have made repairs or upgrades on Hubble from 1993 to 2009, but for the moment, the options are quite limited and there is no real replacement for the Space Shuttle at this time. ;horizon. Boeing's CST-100 Starliner and SpaceX's Crew Dragon are both focused on crew transportation: transporting astronauts to the International Space Station or possibly to others. Until now, their designs do not seem to have the ability to house and support a crew in orbit for several days on a maintenance mission to Hubble, and they do not have the cargo hold or robotic arm of the shuttle. .
The story of Hubble is closely linked to that of the Shuttle program. Shuttle Challenger exploded at its launch in January 1986, taking the life of the entire crew. NASA quickly immobilized the rest of the shuttle fleet while a committee was investigating the tragedy. The planned launch of Hubble in October 1986 was postponed until April 1990. After launch, the $ 1.5 billion telescope would have been an almost complete loss for astronomy if a mission had not been able to install corrective optics. And one last mission in 2009, which removed these optics and replaced several Hubble instruments with improved versions, was delayed much like the launch mission, by the catastrophic loss of a space shuttle – this time. Columbia. And now, with the shuttle program completed in part as a result of Columbia's loss, Hubble is on its own 540 km (340 miles) above Terra Firma.
It's nowhere near
Well, not quite alone; It has remote support from engineers on Earth, who are actively working on finding solutions. And NASA engineers do not easily abandon their scientific robots; NASA is still trying to contact Opportunity, making sure that the dust storm on Mars is slowly dissipating. NASA says Hubble will send home detailed images of the cosmos for years to come. But NASA says it will not happen for years. Just last week, astronomers discovered for the first time a moon in orbit around an exoplanet, thanks to the 19-year-old space telescope. And Hubble still has a decade or two, hopefully, so there could be many more discoveries of this type to come.
And if all goes well, it will be joined in 2021 by the James Webb space telescope. Unlike Hubble, Webb was not designed for shuttle maintenance and will run around 1.5 million kilometers at a point in space called Lagrange's second point, so far from Earth that the gravity of the Earth and that of the Sun sway. . This distance would have put James Webb well beyond a space shuttle mission in case of trouble – but James Webb's design still includes a docking ring, just in case.
