Four hundred years after Galileo used his primitive telescope to find the first moons on Jupiter, astronomers continue to discover more.
The recent discovery of another 12 satellite bodies around the giant planet leaves the total at 79, the largest number of moons of any planet in our solar system.
Experts were looking for objects outside our solar system last year when they oriented their telescopes to the vicinity of Jupiter, said Scott Sheppard of the Carnegie Scientific Institute in Washington. They detected a row of objects loitering near the huge gaseous planet, but they did not know if they were moons or asteroids.
“It was not a sudden discovery, but it took a year to determine what those objects were,“ said Sheppard, who led the team that made the discovery.
It turned out that they were Jupiter’s moons. Last year the identity of two of them was confirmed and on Tuesday the other ten.
A team led by @CarnegiePlanets‘ Scott Sheppard has discovered 12 new moons orbiting Jupiter—11 “normal” outer moons, and one that they’re calling an “oddball.” https://t.co/6zRTPsECVU pic.twitter.com/cKWRuMxDbk
— Carnegie Science (@carnegiescience) July 17, 2018
The moons went unnoticed for so long because they are extremely small, with a diameter of one or two miles, said Gareth Williams of the Minor Planet Center of the Astronomical Institute, who believes that Jupiter has even more of those tiny moons that have not been discovered.
“We just have not observed that area enough,” said Williams, who helped confirm the orbits of the moons.
Experts dubbed one of the “rare” moons because of its unusual orbit. But it was Sheppard’s girlfriend who came up with the official name: Valetudo, the great-granddaughter of the Roman god Jupiter.
Valetudo is in Jupiter’s farthest ring, turning in the opposite direction to the rotation of the planet and against the other moons.
“It’s like I’m going down a street in the opposite direction,” Sheppard said.
The hypothesis is that Valetudo and the similar moons arose shortly after the formation of the planet. Probably at the beginning Jupiter acted like a magnet, attracting all the matter around him. Some of that matter coagulated and was spinning, becoming its moons.
“The amazing thing about these moons is that they are waste from the primary material of the planet,” the expert added.
To confirm the existence of these satellites, telescopes were used in Chile, Hawaii and Arizona.
Galileo detected the four largest moons of Jupiter in 1610. The current total includes eight that have not been seen in recent years. Among the other planets that have more moons are Saturn with 61, Uranus with 27 and Neptune with 14. Mars has two, Earth has one, Mercury and Venus have none.