Impact events on Jupiter

In modern times, numerous impact events on Jupiter have been observed, the most significant of which was the collision of Comet Shoemaker–Levy 9 in 1994. Jupiter is the most massive planet in the Solar System and thus has a vast sphere of gravitational influence, the region of space where an asteroid capture can take place under favorable conditions.^[1]

Jupiter is often able to capture comets that orbit the Sun; such comets enter unstable orbits around the planet that are highly elliptical and perturbable by solar gravity. While some of them eventually recover a heliocentric orbit, others crash into the planet or more rarely become one of its satellites.^[2][3]

In addition to the mass factor, Jupiter's relative proximity to the inner Solar System allows it to influence the distribution of minor bodies there. Dynamic studies have shown that the presence of Jupiter tends to reduce the frequency of impacts on the Earth of objects coming from the Oort cloud,^[4] while it increases the number of impacts of asteroids^[5] and short-period comets.^[6]

For these reasons Jupiter has the highest frequency of impacts of any planet in the Solar System, justifying its reputation as the "sweeper" or "cosmic vacuum cleaner" of the Solar System.^[7] 2018 studies estimate that between 10 and 65 impacts per year of meteoroids with a diameter of between 5 and 20 meters (16 and 66 ft) can occur on the planet. For larger objects capable of leaving a visible scar on the planet's cloud cover for weeks, that study gives an impact frequency of one every 2–12 years. Even larger objects would strike Jupiter every 6–30 years.^[8] 2009 studies suggest an impact frequency of once every 50–350 years for an object of between 0.5 and 1 km (0.31 and 0.62 mi) in diameter; hits from smaller objects would occur more frequently. A 1997 study estimated comets 0.3 km (0.19 mi) in diameter collide with Jupiter once in approximately 500 years and those 1.6 km (0.99 mi) in diameter do so once in every 6,000 years.^[9]