Written by Charlie Sobeck?, Kepler and K2 mission manager
NASA’s Ames Research Center
Moffett Field, CA – NASA mission operations engineers have successfully recovered the Kepler spacecraft from Emergency Mode (EM). On Sunday morning, the spacecraft reached a stable state with the communication antenna pointed toward Earth, enabling telemetry and historical event data to be downloaded to the ground. The spacecraft is operating in its lowest fuel-burn mode.
The mission has cancelled the spacecraft emergency, returning the Deep Space Network ground communications to normal scheduling.Once data is on the ground, the team will thoroughly assess all on board systems to ensure the spacecraft is healthy enough to return to science mode and begin the K2 mission’s microlensing observing campaign, called Campaign 9. This checkout is anticipated to continue through the week.
Earth-based observatories participating in Campaign 9 will continue to make observations as Kepler’s health check continues. The K2 observing opportunity for Campaign 9 will end on July 1st, when the galactic center is no longer in view from the vantage point of the spacecraft.
K2’s previous science campaign concluded on March 23rd. After data was downlinked to the ground, the spacecraft was placed in what is termed Point Rest State (PRS). While in PRS, the spacecraft antenna is pointed toward Earth and it operates in a fuel-efficient mode, with the reaction wheels at rest.
The Emergency Mode began approximately 14 hours before the planned maneuver to orient the spacecraft toward the center of the Milky Way for Campaign 9. The team has therefore ruled out the maneuver and the reaction wheels as possible causes of the EM event. An investigation into what caused the event will be pursued in parallel, with a priority on returning the spacecraft to science operations.
The anomalous EM event is the first that the Kepler spacecraft has encountered during its seven years in space. Mission operations at NASA’s Ames Research Center in California’s Silicon Valley, Ball Aerospace and the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder remain vigilant.
It was the quick response and determination of the engineers throughout the weekend that led to the recovery. We are deeply appreciative of their efforts, and for the outpouring of support from the mission’s fans and followers from around the world. We also recognize the tremendous support from NASA’s Deep Space Network, managed by the Jet Propulsion Laboratory in Pasadena, California, and to NASA’s other missions that surrendered their scheduled telemetry links in order to provide us with the resources needed to protect the Kepler spacecraft.
Updates will be provided as information warrants.
Original April 8th Update: Kepler in Emergency Mode
During a scheduled contact on Thursday, April 7th, mission operations engineers discovered that the Kepler spacecraft was in Emergency Mode (EM). EM is the lowest operational mode and is fuel intensive. Recovering from EM is the team’s priority at this time.
The mission has declared a spacecraft emergency, which provides priority access to ground-based communications at the agency’s Deep Space Network.
Initial indications are that Kepler entered EM approximately 36 hours ago, before mission operations began the maneuver to orient the spacecraft to point toward the center of the Milky Way for the K2 mission’s microlensing observing campaign.
The spacecraft is nearly 75 million miles from Earth, making the communication slow. Even at the speed of light, it takes 13 minutes for a signal to travel to the spacecraft and back.
The last regular contact with the spacecraft was on April, 4th. The spacecraft was in good health and operating as expected.
Kepler completed its prime mission in 2012, detecting nearly 5,000 exoplanets, of which, more than 1,000 have been confirmed. In 2014 the Kepler spacecraft began a new mission called K2. In this extended mission, K2 continues the search for exoplanets while introducing new research opportunities to study young stars, supernovae, and many other astronomical objects.