Although NASA's Kepler spacecraft was once counted down and out after two of its positioning wheels went faulty, some very clever scientists came up with a plan to keep the telescope in commission.
Now, we know that plan worked, as Kepler just discovered a new exoplanet as part of its new K2 mission.
"Like a phoenix rising from the ashes, Kepler has been reborn and is continuing to make discoveries," says Andrew Vanderburg of the Harvard-Smithsonian Center for Astrophysics. "Even better, the planet it found is ripe for follow-up studies,"
Kepler's discovery, a planet dubbed HIP 11645b, was later confirmed by the HARPS-North spectrograph of the Telescopio Nazionale Galileo in the Canary Islands. The planet is about two-and-a-half times the size of Earth and has a short nine-day orbit around its star. This means the planet is probably not habitable, as it would be too hot for life. HIP 11645b is located 180 light-years from Earth in the Pisces constellation.
Kepler spots planets based on something called "transiting," which happens when a planet passes in front of its star. This creates a dimming in the star's light: Kepler measures the resulting brightness. This means that Kepler must maintain a steady position. When two of its positioning wheels failed, Kepler was no longer able to stay stable enough in the sky for these delicate measurements.
However, science came to Kepler's rescue. Now, Kepler uses pressure from the sunlight as a virtual positioning wheel, helping the spacecraft stay steady so it can take its measurements. This means that Kepler now has a new mission, K2, which will continue its search for exoplanets. For a follow-up study by the James Webb Space Telescope, Kepler's new mission also includes the study of stars and star clusters, as well as galaxies and supernovae.
"Last summer, the possibility of a scientifically productive mission for Kepler after its reaction wheel failure in its extended mission was not part of the conversation," says Paul Hertz, NASA's astrophysics division director. "Today, thanks to an innovative idea and lots of hard work by the NASA and Ball Aerospace team, Kepler may well deliver the first candidates for follow-up study by the James Webb Space Telescope to characterize the atmospheres of distant worlds and search for signatures of life."
Before its original mission came to an end, Kepler confirmed nearly 1,000 exoplanets. Since adopting its K2 mission earlier this year, the telescope has observed over 35,000 stars and collected data on them, along with other celestial objects.
[Photo Credit: NASA Ames/JPL-Caltech/T. Pyle]
