Problems with Juno just before flyby

NASA space probe Juno, remaining in space since 2011, performed course correction maneuver after not too lucky flyby on October 19, and will conduct next scheduled flyby close to Jupiter on 11th December 2016.

Juno, which remains on Jupiter orbit since July 4, 2016, is still at the moment on long orbit. It makes possible visiting Jupiter every 53.4 days; last successful flyby took place on September 27, 2016 and NASA planned to collect data from scheduled for 19th October flyby. Unfortunately, Juno appeared to have some problems with onboard computer, which turned probe into safe mode on October 19, 2016, at 05:27 GMT. It caused shutting down all scientific instruments - Juno passed Jupiter on October 19 without collecting any data. To remind, safe mode is state, when only crucial systems of Juno are powered and onboard computer performs self-test. Switching to safe mode is usually resulting of unexpected signal from sensors of the probe. Lockheed Martin and JPL specialists are still evaluating reason for anomaly; one of reasons taken under consideration are assessing engine valves. Signal transmitted from valves could be wrongly interpreted by main computer and it decided to turn on safe mode; still problem is not explained and engineers will continue analyzing data from probe. Luckily, Juno was switched again to normal mode thanks to the recovery command send by specialists from Jet Propulsion Laboratory (which is managing Juno mission) via Deep Space Network 70 m dish. Command was sent on October 24, 2016 with confirmation received at 17:05 GMT.  Not identified problem and entering safe mode probably determined decision of JPL about changing long orbit for 14-days orbit according to original mission plan. It was officially confirmed, that Juno will stay on present orbital position. Two days after recovery from safe mode, Juno performed small correction of present course before last in 2016 next flyby planned for December. At 18:51 GMT on October 26 Juno started its thruster for 31 minutes to change its speed by 2.6 m/s. Leros-1B engine consumed 3.6 kg of hydrazine and nitrogen tetroxide and provided 645 N of thrust. According to NASA, Juno remains in good health and is ready for next flyby planned on 11th December 2016 – shorter distance between Juno and Jupiter will be reached at 16:03 GMT.