Hubble’s Wide Field Camera 3 resumes operations
When camera software detected voltage levels beyond normal range on Jan. 8, 2019, WFC3 immediately entered a safety mode that suspended all operations. In efforts to repair the problem, NASA scientists found voltage levels to be normal, meaning telemetry circuits were releasing erroneous data regarding voltage. They also discovered other errors in engineering data in the same telemetry circuits, confirming the problem was with telemetry and not power supply.
Scientists and technicians reset the telemetry circuits and all related software, and tests following this work produced accurate data on the camera’s engineering. After additional calibration and testing for up to 72 hours, as well as study of data collected before and after the reset, they returned WFC3 to operations mode on Jan. 15.
Two days later, just after noon on, Jan. 17, WFC3 resumed science observations.
Installed on Hubble in May of 2009 during the last shuttle servicing mission (carried out by Atlantis on its only trip to the telescope), WFC3 has captured more than 240,000 images in near infrared, optical light and near ultraviolet light over nearly 10 years, generating over 2,000 peer-reviewed science papers. It has higher resolution and a larger field of view than the instrument it replaced, the Wide Field Planetary Camera 2 (WFPC2).
The ongoing partial U.S. government shutdown that began on Dec. 22, 2018, did not impact the repair process as Hubble and other satellite operations are exempt from any furloughs or funding stoppages.
WFC3 is the most used of all Hubble instruments. Scientists hope their analysis of the data collected before and after the reset will provide answers as to what caused the telemetry errors.
Launched in 1990 aboard Space Shuttle Discovery, Hubble had a predicted lifespan of 15 years; it is is now in its 29th year of operations.
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.