When Galileo first peered through his telescope at Jupiter in 1610, he was shocked to see that the planet was not alone-it was orbited by four moons, a fact that upended then-current theories of astronomy.
If we were to host a system-wide beauty contest among the planets and accepted natural satellites as a valid skill, Jupiter would have a pretty unfair advantage. This new moon, called Valetudo, is a bit of a renegade.
Various groupings of Jovian moons with the newly discovered ones shown in bold. The best forecast, for now, is some time in the next billion years.
Jupiter, it's safe to say, is one of the marvels of our solar system.
Because Jupiter moves across the sky at a known speed, anything nearby moving at the same speed in the same direction becomes a candidate for a moon - but confirmation is a time-consuming process, Sheppard explained to ScienceAlert.
In March 2017, Jupiter was in the ideal location to be observed using the Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile, which has the Dark Energy Camera and can survey the sky for faint objects. Scientists believe that this moon - cosmic shrapnel, caught in the gravity field of Jupiter. It's likely that even more small moons are still waiting to be found. "It's like it's going down the highway in the wrong direction".
Enlarge ImageA look at Jupiter's new moons. Carnegie Institution for Science
But one moon, tentatively dubbed "Valetudo" (green), is an oddball, orbiting with Jupiter's spin but within the retrograde cluster.
The two others are among a closer, inner group that orbit in the prograde, or same direction. Valetudo is the goddess of health and hygiene, which can not help with this little oddball moon's self-confidence. Ganymede, Jupiter's largest moon and the biggest in the solar system, has a diameter of about 5,300 kilometers (about 3,300 miles). Of those, 11 are normal moons while the remaining one is an "oddball". They are also part of a larger group of small moons thought to be the left-over remnants of a once larger moon.
No other planet in the solar system has so many satellites.
It doesn't behave like the other moons, which tend to fall into a few categories. The planet must have acted like a vacuum, sucking up all the material that was around it.?Some of that debris was captured as moons. Unlike other prograde moons, it also crosses paths with the retrograde moons, meaning it has a much higher chance of colliding with them in time.
This Hubble telescope image of the giant planet Jupiter reveals the impact sites of two fragments from comet Shoemaker-Levy 9.
The remarkable chance find brings the gas giant's tally of moons to a whopping 79 compared with 62 for Saturn, the planet with the second most.
Once they finish running and analyzing the simulations, the team plans to publish the results in early 2019. In mythology, she was the great-granddaughter of the Roman god Jupiter.