The surface-dominant ribs on Ganymede, the solar system’s largest moon, may have been caused by a collision with a massive object up to 90 miles/150 kilometers wide.
According to a new paper Publishing From arxiv.org, a dictionary print service of Japanese scientists. If the theory is true, it is the largest impact structure ever identified in the solar system.
Ganymede is the largest of Jupiter’s 79 known moons and is larger than the dwarf planets Pluto and Mercury. Its diameter is 3,273 miles/5,268 km. It is the only moon with a magnetic field. It also has an atmosphere and is suspected to have an underground saltwater ocean.
The surface of Ganymede is dented, grooved and patterned. This paper argues that the furrows across the surface are part of the concentric system of structural ossicles. “If this multi-ring structure is of collision origin, it is the largest collision structure identified in the solar system so far,” the paper reads. “Estimating the size of the impactor is difficult, but an impactor with a radius of 150 km is consistent with the observed furrow characteristics.”
The scientists used images taken in 1979 by NASA’s Voyager 1 and 2 spacecraft and images taken by NASA’s Galileo spacecraft orbiting Jupiter between 2001 and 2003.
NASA’s Juno spacecraft photographed Ganymede during a close flight in June 2021.
This theory may be confirmed by future exploration of Jupiter’s icy moons, in particular the European Space Agency’s JUICE (Jupiter Ice Moon Explorer) mission.
JUICE will be launched as an Ariane 5 rocket from the European Space Airport in French Guiana, South America from April 5 to 25, 2023. It is expected to arrive in 2031 and enter Ganymede orbit in September 2032 after surveying Jupiter’s other moons Europa and Callisto for three and a half years. It will be the first spacecraft to orbit a moon other than Earth’s.
Hope you have clear skies and wide eyes.