Mayday! NASA's Juno Spacecraft Has Engine Trouble in Space

Juno, a solar-powered spacecraft task to observe Jupiter was supposed to go near the biggest and baddest planet in the Solar System this Oct. 19, but due to engine trouble, NASA scientists postponed the supposed flyby to December this year.

Last July 4. Juno entered Jupiter's orbit after a five-year journey from Earth to its host planet. It successfully performed a 35-minute engine burn that slowed down the spacecraft that enabled Jupiter's gravity to allow Juno's entry. The mission already sent some images of Jupiter from its record-breaking first flyby on Aug. 27. The first flyby is the first of 36 close encounters of Juno and Jupiter.

The solar-powered spacecraft has been doing very well since it entered Jupiter's orbit last July 4. It managed to perform one complete flyby and it has also completed orbits around the planet reaching the farthest point of its host planet's orbit. But recent reports say that an engine trouble is causing Juno's mission some delay.

Jupiter is known to have the harshest environment in the Solar System. This means a devastating amount of radiation is present in its atmosphere and Juno is not spared from that. Reports say that the control sent a command that Juno seems to fail to understand last Thursday but it wasn't read correctly by the spacecraft signaling that the radiation in Jupiter might be taking its toll on the spacecraft.

NASA decided to postpone the mission that involves the upcoming burn of Juno's main rocket motor. The Period Reduction Maneuver (PRM) will lessen the days Juno needs to orbit Jupiter from 53.4 to 14 days. The decision was made to perform a thorough check of Juno's valves, a vital part of the spacecraft's fuel pressurization modem.

"Telemetry indicates that two helium check valves that play an important role in the firing of the spacecraft's main engine did not operate as expected during a command sequence that was initiated yesterday," Rick Nybakken, Juno project manager at NASA's Jet Propulsion Laboratory in Pasadena, California said in a press release.  "The valves should have opened in a few seconds, but it took several minutes. We need to better understand this issue before moving forward with a burn of the main engine," Nybakken added.

The decision was finalized after Juno engineers consulted with commercial space flight company Lockheed Martin and NASA's head office in Washington. The burn has to be executed during Juno's closest approach to the planet and the next best window to do that in on Dec. 11, 2016.