The Trojans of Jupiter's orbit and the Lucy probe sent by NASA to investigate them

Jupiter, with a diameter eleven times that of Earth, is the largest planet in the Solar System and the one with the second most satellites, a total of 95.

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A little-known fact to the general public is that there's more moving around Jupiter's orbit than just the giant gas planet. The first of these little-known companions to the Jovian giant was discovered by German astronomer Max Wolf on February 22, 1906: an asteroid named Achilles, 135.5 kilometers in diameter. Since then, thousands of asteroids of various sizes have been discovered orbiting Jupiter, although the actual number is believed to be well over a million.

These asteroids are commonly known as Trojans, which is somewhat ironic considering that the first one was named after a legendary Greek warrior. These Jupiter Trojans are divided into two large groups, which are located at the Lagrange points of that planet (as we saw a month ago, the ghost moons of Mars are also located at these points).

The group of Trojans moving in front of Jupiter is known as the Greek Camp, and more than 8,000 asteroids are already known to be part of it. The aforementioned asteroid Achilles is one of the members of this group, and we also find asteroids named after other famous Trojan War warriors, such as the Trojan Paris (1984, 119 km in diameter) and the Greek Patroclus (1906, 140 km).

The Trojans moving behind Jupiter are known as the Trojan Camp. About 5,000 asteroids are already known within this group. Among them are the Trojan heroes Hector (discovered in 1907 and the largest of the known Jupiter Trojans, at 225 kilometers in diameter) and Aeneas (discovered in 1930 and 140 km in diameter) and the Greek Agamemnon (1919, 131 km).

On October 16, 2021, NASA launched the Lucy space probe, which is on a mission to investigate some of the Jupiter Trojans. This is a very long-duration mission in which the probe will return to the vicinity of Earth in 2031 to perform a gravity assist maneuver. You can learn more about this mission by watching this video published this week by the Astrum channel:

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Main photo: NASA.