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What's the matter with the 12 new Jovian moons? What's the matter with the two "retrogrades"

Astronomers had hoped to find an imaginary planet on the far edge of the solar system, but unexpectedly found 12 new moons around Jupiter, according to National Geographic. What are the 12 new Jovian moons about? What are the 12 new Jovian moons about? The discovery of these satellites was an accident. Now Xiaobian will show you something

These new satellites are different from Titan. Ganymede is the largest satellite in the solar system. They are small, with the smallest diameter of about 1 mile (1.6 kilometers), and orbit Jupiter in strange orbits.

The unexpected discovery of science 'paparazzi'

Last year, Scott Sheppard of the Carnegie Institute of science and colleagues worked to find a planet that might be farther away than Pluto, large enough to have enough gravity to rearrange the orbits of smaller distant objects. Therefore, the team aimed the telescope of Cerro Tololo Inter American Observatory in Chile at some target star regions, hoping to find possible light points moving along the sun's orbit.

During the mission, Shepard and his colleagues found Jupiter within the observation range of the telescope, so they decided to take this opportunity to study Jupiter by the way.

"We use the new camera that was installed on the telescope a few years ago," Shepard said. "It can search large areas faster, so we can cover the entire area around Jupiter with just four images. '

The discovery of these satellites was an accident.

Doug Hemingway, a planetary scientist at the University of California, Berkeley, said: 'it's really interesting. This shows that when you develop the ability to study one thing, you will never know what else you may find next. '

In March 2017, the research team obtained data proving that there may be 10 new satellites, and two other new satellites have been discovered before that. The next month, they observed the signals again. But it will take some time to confirm their orbits. It wasn't until May of this year that the team reconfirmed the existence of all the new moons, bringing the total number of members of the Jupiter satellite family to 79.

Bonnie Buratti of NASA's Jet Propulsion Laboratory said: 'these small outer moons are the most numerous of Jupiter's systems. Adding them to an already large family of satellites doesn't seem like a big discovery. But this is not the case. '

Where does it come from?

The new satellites range in diameter from about a mile (1.6 km) to three miles (4.8 km). Two of the moons are relatively close to Jupiter, and they orbit in the same direction as Jupiter. They are likely to be the debris of a satellite much larger than them that has disintegrated in billions of years since the birth of the solar system.

Nine of these moons form three further clusters and orbit Jupiter retrogradely. Their origins may be similar to those of inner circle satellites: a large satellite with a diameter of about several hundred miles was destroyed after collision and left a pile of debris, some of which continued to orbit Jupiter as its small satellite.

Shepard asked, 'what did they hit? A comet? A stray asteroid? Or other moons in the Jupiter system?'

Another interesting assumption is that the objects that form these small moons are not "indigenous" in the Jupiter system, but attracted by Jupiter's gravity in the early stages of the solar system.

This may sound strange, but it's not uncommon for large planets to pull small objects around over time, especially in the early days of the solar system, when giant planets migrate and disrupt the orbits of objects much smaller than them.

One of Saturn's most famous moons is Enceladus, which comes from the Kuiper belt, which orbits farther than Neptune. Coincidentally, Neptune's most famous moon, Triton I, is also an 'captured' Kuiper belt object.

Bratti points out that 'kinetic scientists believe that the orbits of these outer satellites (at least those captured in the early days) were disturbed by the migration of gas giants. 'we are familiar with gas giants such as Jupiter, Saturn, Uranus and Neptune.

Strange satellite valetudo

Of the 12 new satellites, a strange one is to be named valetudo. Following the astronomical naming convention, its proposed name comes from myth, meaning the Roman goddess of health and hygiene.

Like two new moons that are moving in the right direction, valetudo orbits in the same direction as Jupiter. But relative to Jupiter, its orbit is tilted and located near three retrograde clusters. Thus, Shepard suspects that the formation of these clusters originated from the collision of some satellites with valetudo, the 'remains' of a larger satellite.

He said: 'it's like driving the wrong way on the highway, and there's a high probability of a collision. '

Shepard also studied other giant planets and did not find any new moons around Uranus or Neptune. He was a little disappointed.

He said: 'Uranus is the best object to find a new moon, because you can name it after Shakespeare's character. '