[meteorite-list] New Horizons Team Responds to Spacecraft Anomaly

[Ron Baalke]

http://www.nasa.gov/nh/new-horizons-responds-spacecraft-anomaly

New Horizons Team Responds to Spacecraft Anomaly
July 4, 2015
Last Updated: July 5, 2015
Editor: Lillian Gipson

The New Horizons spacecraft experienced an anomaly the afternoon of July 
4 that led to a loss of communication with Earth. Communication has since 
been reestablished and the spacecraft is healthy.

The mission operations center at the Johns Hopkins University Applied 
Physics Laboratory, Laurel, Maryland, lost contact with the unmanned spacecraft 
-- now 10 days from arrival at Pluto -- at 1:54 p.m. EDT, and regained 
communications with New Horizons at 3:15 p.m. EDT, through NASA's Deep 
Space Network. 

During that time the autonomous autopilot on board the spacecraft recognized 
a problem and - as it's programmed to do in such a situation - switched 
from the main to the backup computer. The autopilot placed the spacecraft 
in "safe mode," and commanded the backup computer to reinitiate communication 
with Earth. New Horizons then began to transmit telemetry to help engineers 
diagnose the problem.  

A New Horizons Anomaly Review Board (ARB) was convened at 4 p.m. EDT to 
gather information on the problem and initiate a recovery plan. The team 
is now working to return New Horizons to its original flight plan. Due 
to the 9-hour, round trip communication delay that results from operating 
a spacecraft almost 3 billion miles (4.9 billion kilometers) from Earth, 
full recovery is expected to take from one to several days; New Horizons 
will be temporarily unable to collect science data during that time.

Status updates will be issued as new information is available.