Juno Flies Past Ganymede and Jupiter

18 Jul 2021

OSR blog post

NASA’s Juno spacecraft completed its 34th flyby of Jupiter. Read below what researchers have learned up to this point.

On June 7, 2021, NASA’s Juno spacecraft flew closer to Jupiter’s ice-encrusted moon Ganymede than any spacecraft in more than two decades. Images captured by JunoCam were processed into time-lapse animation by citizen scientist Gerald Eichstädt. The video has excited the scientific community.

Juno Takes A Closer Look

Jupiter orbiter’s JunoCam imager took some of the photos. The Stellar Reference Unit star camera took pictures as well. Both show the surface in remarkable detail. For example, it shows that the surface has cratered. Furthermore, it has clearly distinct dark and bright terrain. The pictures also lead to speculation that long structural features may come from tectonic faults.

Scientists believe that Juno’s encounter with the Jovian moon will yield insights into its composition. Further, they hope to learn more about its ionosphere, magnetosphere, and ice shell. Studies of data from the flyby may also provide measurements of the radiation environment.

The video reveals stunning images of several of Jupiter’s atmospheres. For example, it shows the circumpolar cyclones at the north pole. In addition, it shows five of the gas giant’s eight massive storms rotating counterclockwise in the southern hemisphere. They appear as white ovals, which scientists have nicknamed “string of pearls.” Finally, using information that Juno has learned from studying Jupiter’s atmosphere, the animation team simulated lightning. This lightning comes from Jupiter’s giant thunderstorms.

Ganymede and Jupiter Video

Utilizing imagery captured by the probe’s JunoCam, mission researchers stitched together an animation. They call it the “starship captain” point of view of Ganymede and Jupiter. The footage shows in amazing detail the ice-encrusted moon’s dark and light regions. In addition, it shows the Tros crater scar. “The animation shows just how beautiful deep space exploration can be,” said Juno Principal Investigator Scott Bolton. “The animation is a way for people to imagine exploring our solar system firsthand by seeing what it would be like to be orbiting Jupiter and flying past one of its icy moons. Today, as we approach the exciting prospect of humans being able to visit space in orbit around Earth, this propels our imagination decades into the future, when humans will be visiting the alien worlds in our solar system.”

The 3:30-minute-long animation begins with Juno approaching Ganymede, passing within 645 miles (1,038 kilometers) of the surface. It races along at a relative velocity of 41,600 mph (67,000 kph). The imagery shows several of the moon’s dark and light regions. The darker regions are believed to result from ice sublimating into the surrounding vacuum. This vacuum leaves behind a darkened residue. In addition, it shows the crater Tros, which is among the largest and brightest crater scars on Ganymede.

It takes just 14 hours, 50 minutes for Juno to travel the 735,000 miles (1.18 million kilometers) between Ganymede and Jupiter. The viewer is transported to within just 2,100 miles (3,400 kilometers) above Jupiter’s spectacular cloud tops. By that point, Jupiter’s powerful gravity has accelerated the spacecraft to almost 130,000 mph (210,000 kph) relative to the planet. (NASA, 2021)

Juno will complete several more missions in the coming years. NASA plans to send it past three moons through 2025.