Juno Passes by Earth, Emerges in Safe Mode

NASA’s Jupiter-bound Juno spacecraft received a gravity-assist from Earth today, but emerged from the encounter in safe mode.  It remains on its trajectory to Jupiter, but what caused it to switch into a mode that protects its safety is unknown.

Launched in 2011, the $1.1 billion Juno spacecraft is making its way to Jupiter using a gravity assist from Earth, which it received today.  The spacecraft  is expected to reach Jupiter in 2016 and make 33 orbits of the giant gas planet over a 14 month period.  It then will “crash” into Jupiter to ensure it does not accidentally impact any of Jupiter’s moons, some of which are considered potential havens for life.

Juno’s Earth swing-by took place today.  At the start, everything appeared normal.   Juno went through an expected 22 minute radio blackout phase, reemerging in safe mode to the surprise of project leaders.  Engineers do not know what triggered it. The Denver Post quotes Tim Gasparrini, Juno program manager for Lockheed Martin, as saying “There’s always a chance the spacecraft will do something unexpected.”

Scott Bolton of the Southwest Research Institute (SwRI) is principal investigator for the mission.  The spacecraft was built by Lockheed Martin and the mission is managed by JPL.  NASA’s website for this mission is down because of the government shutdown.   SwRI’s Juno website is still functioning, but at the moment does not seem to include information about this problem.

Emily Lakdawalla of the Planetary Society posts on her blog that JPL’s Juno Project Manager Rick Nybakken says that JPL has established communications with the spacecraft and they have “full commandability” and it is in a “safe, stable state.”