Space

Kepler malfunction may end planet-hunting mission

Kepler malfunction may end planet-hunting mission
Artist's impression of Kepler (Image: NASA)
Artist's impression of Kepler (Image: NASA)
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Graphic of Kepler (Image: NASA)
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Graphic of Kepler (Image: NASA)
Artist's impression of Kepler (Image: NASA)
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Artist's impression of Kepler (Image: NASA)

NASA’s Kepler space mission may be coming to an unexpected end. The space agency announced on Wednesday that the spacecraft, designed to seek out possible earth-like extraterrestrial bodies, has suffered a malfunction that may make it impossible to carry on with its search.

The problem appears to be a failure of a gyroscope, also called a reaction wheel. The spacecraft is now oriented with its solar panels facing the Sun as it slowly spins with communications being regularly interrupted as its antenna turns away from Earth. NASA has attempted to regain normal control, but with little success.

Kepler has been having attitude control problems recently and is in what is called “Thruster-Controlled Safe Mode” where control is shifted from the wheels to the spacecraft’s thrusters. NASA has been attempting to get all of the craft’s reaction wheels running properly, but number four wheel remains at full torque with the spin rate dropped to zero. This indicates that there has very probably been a structural failure of the wheel bearing.

Graphic of Kepler (Image: NASA)
Graphic of Kepler (Image: NASA)

Currently, mission control is making preparations to move Kepler into a Point Rest State during which the craft will be loaded with new software for loosely pointing in a way that allows its attitude to be controlled with minimum thruster use, yet maintaining constant communications on the X-band radio link. This will allow Kepler to conserve fuel for a period of years, but if the wheel cannot be brought back into operation, Kepler’s planet hunting mission will be at an end.

Launched in 2009, the Kepler spacecraft is tasked with finding planets orbiting other stars, with a particular focus on potentially habitable Earth-like planets. So far, it has detected 2,740 candidates and 122 planets have been confirmed. Without the ability to maintain exact attitude control in pointing its telescope, it will be unable to continue its photometric survey which, to put it mildly, would be a terrible shame.

Source: NASA

6 comments
6 comments
Rocky Stefano
A terrible shame? You know for the kind of money it took to build it, around 550m of taxpayer dollars, you think that the engineers could have built in some redundancy (you know like they always claim to do) for the steering of the bloody thing.
Phil
The primary mission ended Nov 2012 after 3-1/2 years. It is now in extended mission mode. Darn right it is a shame it cannot be used any more for searching for planets, however we have sufficient information now to understand that there are many planets out there that one day could be explored. I hope that with the information so far collected, and with advancing technology, possibly in the future we can use ground based search telescopes to accomplish the same as Kepler.
Max Orbit
Rocky: It's easy to be an armchair quarterback. Having spent 20 years designing these things, I can tell you that every failure mode was thoroughly investigated and addressed. There are some things that just don't lend themselves to redundancy. Would you want 8 tires on your car just to avoid a flat, knowing it would reduce your gas mileage by 50%, and cost twice as much to replace? It could very well be that a micro meteor found its way into the mechanism, and there is no way to design for that. There are budget limitations, and it met its initial mission objectives. Pop another top and go back to the NFL game.
StWils
That Kepler can be put into a low-energy parking state provides time to put together a robotic mission to go get Kepler and bring it back to where it can be worked on. Then with a successful repair, returned to duty as originally intended. Such a mission reconfiguration was not considered when Kepler and other devices were designed but is becoming a progressively more possible, realistic, and affordable choice. These mission profile changes are going to progressively enabled as faster, better, cheaper trips to LEO orbits come online.
Nairda
That's code for: "Found inhabited planetary system. Inhabitants communicated in no uncertain terms they do not want their sector to be mapped"
Fritz Menzel
LOL, Nairda — makes me wish there was a "Like" button in this forum. Totally agree with Max Orbit's comments. Kepler has done its job; those who expect so much more are just a little spoiled.