Ten newly found moons of Jupiter include a 'wrong-way driver'

  • Ten newly found moons of Jupiter include a 'wrong-way driver'

Ten newly found moons of Jupiter include a 'wrong-way driver'

From Jupiter's entire collection of 79 moons, Sheppard has been involved in the discovery of 54 of them, including most of the known retrograde moons.

The researchers discover new Solar System bodies, and calculate their orbits, by photographing the same part of the sky weeks or months apart.

Jupiter has dozens and dozens of moons in its orbit, but another 12 has just been discovered - including an "oddball" with a precarious orbit.

Gareth Williams, an astronomer at the Harvard-Smithsonian Center for Astrophysics and director at the International Astronomical Union's Minor Planet Center, predicted that "there aren't any bigger objects undiscovered out there" around Jupiter.

"We had to observe the new candidate Jupiter moons again a month later and again a year later to confirm they were actually orbiting Jupiter and thus were moons of Jupiter", he said.

This illustration shows the newly discovered moons of Jupiter and their orbits.

The new moons, reported in The International Astronomical Union's Minor Planet Center's Electronic Circular, were first found by a team of US astronomers in March 2017 while they searched the skies for signs of Planet 9, a hypothesized ninth planet orbiting the sun far beyond Neptune.

Before Sheppard's team conducted their survey, there were 69 known Jovian moons, but there's always been reason to believe there are quite a few more.

The nine retrograde moons recently found in Jupiter's orbit go around the planet in roughly two years.

Jupiter's moons range in size from shrimpy satellites to whopping space hulks. It's believed these moons are the remnants of larger space rocks that broke apart during collisions with asteroids, comets or other moons.

"Valetudo" is like driving down the highway on the wrong side of the road", astronomer Scott S. Sheppard, a staff scientist at the Carnegie Institution for Science in Washington and the leader of the team of astronomers who made the discovery, told NBC News MACH in an email.

This interest in finding new moons around Jupiter wasn't just a spur of the moment decision for Sheppard. Only in today's much emptier solar system, after the giant planets finished forming and clearing their surroundings of gas and dust, would small moons like these have been able to survive.

Since Valetudo is moving in the opposite direction to the other retrograde moons, there is a greater chance of a collision occurring, and is probably inevitable. One possibility is NASA's Europa moon mission planned in the late 2020s or early 2030s.

The moons are remnants of what was out there, born in the disc of gas and dust around Jupiter after the planet formed and then captured and pulled into Jupiter's orbit. Sheppard's girlfriend came up with a name for it: Valetudo, the great-granddaughter of the Roman god Jupiter. After a year-study, they have now confirmed that the bodies were locked in orbit around the gas giant. The first four moons were discovered by Galileo in 1610. The irregular satellites didn't form around Jupiter in the same way that the planets formed around the Sun, or the regular satellites around Jupiter, from a flat disc in a prograde orbit. That's how many moons astronomers have now identified orbiting the planet Jupiter.