A massive asteroid impact on Ganymede, the largest moon in our solar system, is believed to have occurred around 4 billion years ago. According to researchers, the asteroid was approximately 185 miles across and struck the moon at an angle of 60-90 degrees. The impact created a crater up to 1,000 miles wide and had significant effects on Ganymede’s surface.
The research suggests that the asteroid strike caused Ganymede to spin around its axis such that the impact site is now located almost directly away from Jupiter. This reorientation is thought to have occurred due to the added weight of the impact zone, destabilizing the moon and causing it to swing around on its axis.
Ganymede’s surface features distinctive furrows that were previously believed to be remnants of multiple concentric rings created by the giant asteroid impact. However, it was unclear how big the impact was and what effect it had on the Jovian moon. The new research provides insights into the impact’s size and implications for Ganymede.
The study’s findings have significant implications for our understanding of Ganymede’s surface and interior. The impact would have “completely removed the original surface” and affected the moon’s interior, which scientists believe contains a hidden saltwater ocean.
Further evidence may come from the European Space Agency’s Juice probe, which is set to explore Jupiter and its moons, including Ganymede. The mission aims to search for pockets of water and sources of energy essential for life on the Jovian moons.
Source: https://www.theguardian.com/science/article/2024/sep/03/jupiter-moon-ganymede-struck-asteroid-bigger-dinosaurs