And there is one very strange copy ...
With the twelve new moons, the total number of moons around Jupiter is 79. It means that Jupiter is a record holder: no other planet in our solar system has so many moons. Jupiter smuggles a bit; at least eleven of the twelve moons that researchers have discovered seem to be fragments of moons that were once much larger.
Nine of the twelve discovered moons are part of a swarm of moons that move around Jupiter in a retrograde orbit. It means that the direction of rotation of Jupiter is exactly opposite to the direction in which the moons move. It takes the nine moons in that retrograde job about two years to complete a round around Jupiter. Furthermore, these nine moons can be subdivided into three groups that can be distinguished from one another and this suggests that they are the remains of three larger celestial bodies that - either due to collisions with other moons or asteroid and comet impacts - have been broken into pieces.
Then there are also two moons that do move in the same direction as Jupiter itself. These moons are a bit closer to the gas giant and need less than a year to complete a round around Jupiter. These two moons too seem to be remnants of a larger moon that has been broken to pieces for whatever reason.
Stranger in our midst
In addition to these eleven moons, the researchers have found another one and this is really a strange duck. Researcher Scott Sheppard calls the moon "eccentric". “It has a job that cannot be compared to that of other moons around Jupiter. With a diameter of less than 1 kilometer, it is also the smallest moon that is known around Jupiter. with a retrograde, or exactly opposite, orbit. It means that Valetudo has oncoming traffic. "This is an unstable situation," said Sheppard. The chance of frontal collisions is high. "Frontal collisions would quickly disintegrate the objects." The researchers think that this eccentric moon is also a remnant of a much larger moon that once collided with the big moon from which the nine retrograde orbits arose.
Image: Carnegie Institution for Science / Roberto Molar Candanosa.
Researchers discovered the moons more or less by accident. In fact, as part of the search for planet X, they were looking for celestial bodies on the edge of our solar system. "Jupiter happened to be in the night sky near the area where we were looking for extremely distant objects in our solar system," Sheppard says. "So we happened to be able to search for new moons around Jupiter while at the same time searching for planets on the edge of our solar system for planets."