The issue: It can’t aim anymore, but it can still see
Though NASA last week scrapped efforts to restore the crippled Kepler spacecraft to full working order, the space telescope project — one of the most successful scientific missions ever — almost certainly will continue to yield discoveries.
THE SPACECRAFT in 2009 undertook “a search for habitable planets,” as NASA’s website notes. Kepler was guided by four gyroscope-like reaction wheels that kept the telescope focused in one direction with an accuracy that scientists compared to zeroing in on a soccer ball in San Francisco from New York’s Central Park.
One of those reaction wheels failed last year and defied scientists’ attempt to repair it from afar. The craft could function with three wheels, but a second one failed in May, rendering the craft useless as a planet hunter. While the telescope itself remains in perfect condition, any discovery depends on something interesting wandering across its static field of vision.
Kepler confirmed 135 exoplanets in the Milky Way, some of them similar in size and orbit to Earth, and identified more than 3,500 “candidate” planets, bodies awaiting a positive classification.
Among Kepler’s more interesting findings, according to The New York Times: a planet with two suns, dubbed Tatooine after a similar planet in “Star Wars,” and a so-called Styrofoam planet half as large as Jupiter but only a tenth as dense.
EVEN THOUGH the Kepler spacecraft is now largely inoperable, NASA considers its backlog of data a treasure trove. NASA plans to keep trying to salvage the mission, which already has surpassed its projected four-year lifespan. Given NASA’s advances in technology, repairing or retrieving Kepler may not be out of the question — especially if there’s adequate money.
William Borucki, a scientist who is Kepler’s principal investigator at NASA’s Ames Research Center in California, said the mission proves our galaxy is “filled to the brim with planets,” many of them the size of Earth.
Kepler made one thesis much more likely: We are not alone.