May 16, 2013
Can A Stanford Professor Revive The Defunct Kepler Space Telescope?
Lee Rannals for redOrbit.com - Your Universe Online
Scott Hubbard, a consulting professor of aeronautics and astronautics, helped guide the Kepler mission when he served as director of NASA Ames Research Center. He has devised a few plans for the space agency that could potentially help bring the planet-hunting spacecraft back to life.
NASA said its Kepler spacecraft was sitting in safe mode, possibly putting an end to its mission. The observatory went into a Thruster-Controlled Safe Mode and the space agency hasn´t been too optimistic about being able to bring it back online.
Hubbard said the Kepler spacecraft's photo-detector array registers more than 100,000 stars at a time, and in order to detect exoplanets, it must remain extremely steady so that the stars do not wander across the optics. At least three of Kepler's four gyroscope-like reaction wheels need to be functioning to keep Kepler stable, but the spacecraft currently only has two wheels left.
"There are two possible ways to salvage the spacecraft that I'm aware of," Hubbard said. "One is that they could try turning back on the reaction wheel that they shut off a year ago. It was putting metal on metal, and the friction was interfering with its operation, so you could see if the lubricant that is in there, having sat quietly, has redistributed itself, and maybe it will work."
He said the other scheme involves using thrusters and the solar pressure exerted on the solar panels to try and act as a third reaction wheel and provide additional pointing stability.
"I haven't investigated it, but my impression is that it would require sending a lot more operational commands to the spacecraft," the professor added.
Some believe that if Kepler isn't brought back to full functionality, there is still a chance it could be used to detect asteroids. Hubbard, however, says that might be jumping the gun.
"Whether or not it could function as a detector for asteroids is something that would have to be studied, but since it wasn't built as a camera, I would say that I'm skeptical. That said, certainly between Ames Research Center and the Jet Propulsion Laboratory, they've got the best people in the world working on it," he said.
For now, scientists will need to rely on the year-and-a-half's worth of data from the Kepler mission that´s still waiting for analysis.
"It's important to make clear, though, that in the original queue of missions aimed at finding life elsewhere, a mission like Kepler was a survey mission to establish the statistical frequency of whether these planets are rare or common. It lived the length of its prime mission, and was extremely successful during that time at achieving this goal," Hubbard said.
"It has paved the way for additional missions, such as TESS — Transiting Exoplanet Survey Satellite — and TPF — Terrestrial Planet Finder — which will continue the search for Earth-like exoplanets in the near future."