A group of scientists led by Scott Sheppard from the Carnegie Institute (USA) discovered 12 new satellites of Jupiter, thus increasing the number of moons in the gas giant to 79. At the same time, one of the objects, named Valetuda in honor of the ancient Roman goddess of health and hygiene, has unusual unstable orbit. This was announced in a press release on the Phys.org website.
According to the researchers, the discovery came when they were looking for distant massive objects that are believed to be in the orbit of Pluto (for example, a hypothetical ninth planet). Jupiter and its satellites were close to the field of view of astronomical instruments, which made it possible to observe the previously unknown moons of the giant planet.
Astronomers have discovered 12 new satellites, including a small object a kilometer in diameter. Nine moons, forming a group and being, most likely, fragments of a larger celestial body, move in a retrograde orbit, that is, in the direction opposite to the direction of Jupiter's rotation around its axis. Another group is formed by two satellites that are closer to the gas giant, and their rotation coincides with the rotation of the planet.
The last moon, which is probably the smallest known satellites of Jupiter, also has an orbit that coincides with the rotation of the planet, which, however, crosses the orbits of retrograde objects. There is a high risk that Valetuda will collide with another celestial body and cease to exist. Scientists believe that it is a fragment of a large rotating object in the same direction as Jupiter, the destruction of which led to the appearance of retrograde moons.