On Monday, Jupiter’s moon Ganymede will have a visitor from Earth. Above the surface of the solar system’s largest moon at 1:35 p.m. ET, NASA’s Juno spacecraft will zoom by, just 645 miles. Since the Galileo mission flew by in 2000, it is the 1st time a probe has made a close-up visit to Ganymede. It is an icy moon, and from planetary scientists these days, icy moons attract a lot of attention.
Ice is not unusual on moons, and even on Earth’s Moon, some ice is there. A significant amount of water is there in large moon around other planets, and under their icy surfaces, some are thought to have liquid oceans. As per researchers, even though they are far from the Sun, these watery worlds could be home to some life.
Scientists used to think that the heat used to come from the planet stars, in Earth’s case Sun. I think we’ve realized in the last few decades that the idea of habitability has extended,” says Scott Bolton of the Southwest Research Institute, who is the principal investigator for the Juno mission. One feature that Ganymede has other icy moon lacks. “Ganymede is the only one that has its own magnetic field,” says Katherine de Kleer, a planetary scientist at Caltech.
Earth’s magnetic field protects us from charged particles coming from Sun. The magnetic field of Ganymede does something similar. According to Kleer, all of this material that’s come off of Io Ganymede’s surface is being protected. It is among the four more giant moons of Jupiter, and Io is the innermost moon which is volcanically active. It is not clear that this protection increases the chance of finding some life on Ganymede.
Juno’s Microwave Radiometer will provide information about Ganymede’s water-ice crust in addition to studying the magnetic field. The interaction between the moon’s thin atmosphere and the charged particles that rain down on Ganymede, the instrument will study. Other instruments will examine the aurorae on Ganymede.