After a short period of uncertainty as to the fate of NASA's premier exoplanet hunter, communications with the Kepler space telescope have been resumed and hopes are high that the embattled mission will soon get back to the business of finding alien worlds.
NEWS: Kepler Suffers Unknown Technical Problem
Problems began for Kepler when mission scientists checked in with the spacecraft on Thursday. Some time between April 4 and April 7, its onboard systems switched into an "Emergency Mode," the first time in its 7 year history this has happened. Spacecraft are complex and many fail-safes are designed into their systems; should one of those fail-safes be triggered, the spacecraft can autonomously drop into a low-power state to avoid further damage.
Kepler was already in a low power standby state after pausing its "K2″ mission before being turned toward our galactic core to begin a new and exciting phase - to seek out orphan planets. But when Kepler didn't communicate with the ground during a scheduled check-in, the NASA team realized something was awry.
MORE: Kepler's New Mission: To Hunt Strange Orphan Worlds
Kepler was launched in 2009 and since then has identified hundreds of extrasolar planets (or exoplanets) orbiting other stars, but in 2013 the spacecraft suffered failures of 2 of its 4 gyroscopes. To maintain its position in space, ensuring it is steadily focused on the same region of the sky, Kepler needed at least 3 of its gyroscopes to be in operation. When its second failed, mission scientists came up with an ingenious plan to begin a new phase of planet hunting, known as K2. Using solar wind pressure, in combination with the two working gyroscopes, Kepler has widened its search for exoplanets.
In collaboration with ground-based observatories, the K2 mission was going to begin yet another voyage of discovery, by slewing Kepler to point at the Milky Way's core in an effort to seek out worlds that have been separated from their parent stars and become interstellar orphans. Kepler will continuously stare at the galactic bulge, looking for transient brightenings of stars - known as microlensing events. These events occur when a free-flying planet passes in front of a distant star, slight warping of spacetime around the planet briefly magnifying the starlight. This K2 project is part of "Campaign 9."
NEWS: Orphan Planet May Have Estranged Parent Star
But 14 hours before Kepler was going to be commanded to turn toward the galactic core, the Emergency Mode was triggered and mission scientists were at a loss to work out what happened.
Now that Kepler appears to be functioning and talking to mission control, mission engineers will be working hard to work out why the Emergency Mode was triggered while prepping the space telescope to recommence science operations.
Fingers crossed this particular glitch was an isolated event and Kepler can get back to seeking out some of the strangest and mysterious alien worlds that exist in our galaxy: exoplanetary orphans.