New Horizons put in final hibernation before 2019 KBO flyby
At 9:31 a.m. EST (14:31 GMT) on December 21, 2017, the probe, following commands uploaded to it just one week earlier, entered hibernation mode, a state in which it will remain until June 4, 2018.
While the spacecraft’s onboard flight computer stays active during hibernation periods, monitoring system health and sending beacon status tones back to Earth once a week, most of the probe’s equipment is powered down when in hibernation mode.
A report on the safety and health of the spacecraft is sent to Earth once per month.
During this hibernation period, New Horizons scientists will plan the MU69 flyby sequence in detail, setting computer commands for observation of the KBO by the spacecraft’s seven science instruments at the time of the flyby.
Meanwhile, commands already uploaded to the onboard flight computer will perform any necessary course correction maneuvers, gather science data about the Kuiper Belt environment, and wake up the probe next June, at which time it will monitor the status of the spacecraft’s critical systems.
New Horizons is currently about 3.8 billion miles (almost 6.2 billion km) from Earth. Radio signals sent to and from the spacecraft take five hours and 42 minutes each way traveling at the universal speed of light.
Messages are sent to and from NASA’s Deep Space Network (DSN) outside of Madrid, Spain.
Once woken up, New Horizons will be kept awake through the end of 2020 until all the data collected during the January 1, 2019, encounter is returned to Earth for study and analysis.
Anyone interested in tracking the spacecraft and seeing its current location can do so at the mission’s “Where is New Horizons” website.
Laurel Kornfeld is an amateur astronomer and freelance writer from Highland Park, NJ, who enjoys writing about astronomy and planetary science. She studied journalism at Douglass College, Rutgers University, and earned a Graduate Certificate of Science from Swinburne University’s Astronomy Online program. Her writings have been published online in The Atlantic, Astronomy magazine’s guest blog section, the UK Space Conference, the 2009 IAU General Assembly newspaper, The Space Reporter, and newsletters of various astronomy clubs. She is a member of the Cranford, NJ-based Amateur Astronomers, Inc. Especially interested in the outer solar system, Laurel gave a brief presentation at the 2008 Great Planet Debate held at the Johns Hopkins University Applied Physics Lab in Laurel, MD.