Kepler has suffered a malfunction, but NASA says the spacecraft will still be able to complete its mission.
Kepler was launched into space in March of 2009 with the three and a half-year mission to determine how common Earth-like planets were in our galaxy. Two months ago, however, a malfunction aboard the spacecraft halted the search for exo-planets, and it is unlikely that Kepler will be able to recover from the glitch. Thankfully, NASA says the mission goal is likely already attainable.
“We believe we do have enough data to answer the question,” said Jon Jenkins of the SETI (Search for Extraterrestrial Intelligence) Institute, “Now, we won’t have as tight error bars as we would otherwise have, and we won’t have orbital periods out well beyond Earth’s in terms of Earth-size planets, but we’ll still do a credible job and a good enough job delivering the answers that we need.”
Kepler spots exo-planets by monitoring the brightness of their parent stars. When a planet passes in front of its sun, it causes a dip in the brightness of that star by covering it. Kepler needs three such dips in brightness in order to flag the system as having an exo-planet. Unfortunately, the farther the planet is from the star, the longer it takes to orbit. this means some planets can take years to verify.
Since this is precision work, Kepler has four onboard gyroscopic “reaction wheels” to stay on target and track the 150,000 stars it’s monitoring; three of these wheels are for standard use and one is a spare in case of failure. The number two wheel on the Kepler broke last year, and in May of this year, the number four wheel malfunctioned. With only one spare, this put the Kepler out of service.
Poor little Kepler isn’t feeling too well
Engineers at NASA are working on potential fixes and will begin sending repair commands to the craft within the next week or two. Manned repair is unfortunately not an option: The Kepler orbits the Sun, rather than the Earth, meaning it’s currently millions of kilometers away.