NASA’s Juno Preps For Fourth Jupiter Flyby, All 8 Science Instruments To Be Switched On

NASA’s solar-powered Juno spacecraft will make its fourth flyby of Jupiter on Thursday morning, the space agency announced Wednesday. During its closest approach in the upcoming flyby, at 7:57 a.m. EST, the spacecraft will be roughly 2,670 miles above the gas giant’s cloud tops, travelling at a speed of about 129,000 miles per hour.

During this flyby, which comes almost two months after the previous one, all eight of Juno’s science instruments will be switched on.

“Tomorrow may be ‘Groundhog Day’ here on Earth, but it’s never Groundhog Day when you are flying past Jupiter,” Juno Principal Investigator Scott Bolton from the Southwest Research Institute in San Antonio, Texas, said in a statement. “With every close flyby we are finding something new.”

Juno was launched in August 2011 and traversed nearly 2 billion miles of space to reach Jupiter. The primary goals of the $1.1 billion mission are to find out whether Jupiter has a solid core, how its atmosphere and magnetosphere formed, and whether there is water in the gas cloud shrouding the planet — information that may not only provide vital clues to how the planet formed and evolved, but also to how the solar system we live in came into existence.

In total, Juno, currently locked in a 53-day orbit around Jupiter, is expected to perform three dozen flybys over the next one and a half years.

Although the science instruments on board Juno collected data during the first close pass over Jupiter in August, revealing that the planet’s magnetic fields and aurora are bigger and more powerful than originally thought, they failed to do so during the second flyby in October, when the spacecraft unexpectedly went into a safe mode. However, Juno successfully completed its third close flyby Dec. 11, when seven of its science instruments and the JunoCam — a high-resolution color camera specially designed to work on a spinning spacecraft — were switched on.

“The Juno science team continues to analyze returns from previous flybys,” NASA said in the statement. “Revelations include that Jupiter’s magnetic fields and aurora are bigger and more powerful than originally thought and that the belts and zones that give the gas giant’s cloud top its distinctive look extend deep into the planet’s interior.”

Several peer-reviewed papers analyzing science data gathered during the first three flybys are expected to be published in the coming weeks and months.

At the end of its mission, Juno will dive into Jupiter’s atmosphere and burn up — a “deorbit” maneuver that is necessary to ensure that it does not crash into and contaminate the Jovian moons Europa, Ganymede and Callisto.