NASA on June 7, 2018 approved an extension of Juno’s science operations until July 2021. This provides the space probe with an additional 41 months in orbit around Jupiter.
The decision was taken after an independent panel of experts confirmed in April that Juno is on track to achieve its science objectives and is already returning spectacular results. The spacecraft and all its instruments were reported to be in good health and operating nominally.
The probe will complete its two-year anniversary of being in the orbit of Jupiter in July 2018.
The extension of its operations will enable Juno to achieve its primary science objectives.
The larger orbits will also allow the scientists to further explore the far reaches of the Jovian magnetosphere, the region of space dominated by Jupiter's magnetic field including the far magnetotail, the southern magnetosphere and the magnetospheric boundary region called the magnetopause.
• NASA has now funded Juno through FY 2022. The spacecraft was supposed to end its mission by crashing into Jupiter's atmosphere in July this year.
• The end of prime operations is now expected to be in July 2021, with data analysis and mission close-out activities continuing into 2022.
• The spacecraft is in 53-day orbits rather than 14-day orbits as initially planned because of a concern about valves on the spacecraft’s fuel system.
• The longer orbit means that it will take more time to collect the needed science data.
• Juno will make its 13th science flyby over Jupiter's mysterious cloud tops on July 16.
• The Juno spacecraft entered the orbit of Jupiter on July 4, 2016, entering a 53-day checkout orbit.
• The spacecraft was supposed to complete two 53-day orbits before performing an engine burn to reduce the spacecraft’s orbital period and apojove (farthest point in the craft’s orbit of Jupiter) to its planned 14-day science orbit.
• The engine burn, called the Period Reduction Maneuver, was planned for October 18, 2016. However, during the second 53-day checkout orbit, just 4 days before the scheduled engine burn, NASA engineers while going through tests of Juno’s primary engine spotted something in the data that gave them cause for concern.
• The engineers found that two helium check valves that play an important role in the firing of the spacecraft’s main engine did not operate as expected. The valves that should have opened in a few seconds took several minutes.
• The data on the valves indicated that it was too risky to attempt ignition of the engine hence, NASA decided to leave Juno in its 53-day orbit, significantly changing the mission outlook and timing of its science operations.
• From the pre-launch criteria of completing 12 science gathering dives close to Jupiter’s atmosphere, within six months of entering into the planet’s orbit, Juno has completed only 9 such dives in one and half years.
• Under the originally planned mission timeline, Juno would have completed 37 total orbits of Jupiter, two 53 day checkout orbit and 34 science orbits by July 2018 before embarking on its final journey for a destructive plunge into Jupiter’s atmosphere 53 days later.
• Juno, the NASA space probe was launched on August 5, 2011, as a part of NASA’s New Frontiers program to begin a scientific investigation of Jupiter.
• The spacecraft was managed by NASA's Jet Propulsion Laboratory and built by Lockheed Martin Space.
• It successfully entered the polar orbit of Jupiter on July 5, 2016.
• The spacecraft’s primary goal was to gain data on the story of Jupiter's formation and evolution, including whether it has a rocky core and to measure the amount of water present within the deep atmosphere.
• It aimed to observe and measure Jupiter's gravity and magnetic fields, mass distribution, atmospheric dynamics and composition and evolution using long-proven technologies.
• Juno is the second spacecraft to orbit Jupiter, after the nuclear powered Galileo orbiter, which orbited the gas planet from 1995 to 2003.