- nasa.gov
The small body rotates Jupiter in a prosperous orbit, but at a distance that puts it in the path of other moons that orbit in the opposite direction.
One of more than a dozen newly discovered moons around Jupiter is circling the planet in a suicidal orbit that will inevitably lead to its violent destruction, astronomers report.
US researchers stumbled upon the new moons while searching for a mysterious ninth planet or Planet X well beyond the orbit of Neptune, which is considered the most distant planet in the solar system (why do they hate on Pluto?).
The team first observed the moons in March last year, from the Cerro Tololo Inter-American Observatory in Chile, but it took more than a year to confirm that the bodies were in orbit around the gas giant. “It takes several observations to confirm an object actually orbits around Jupiter,” Williams said. “So, the whole process took a year.” Scott Sheppard, who led the study at the Carnegie Institution in Washington , said in a statement.
Jupiter, the largest planet in the solar system, barely had moons before the last finds. The recent increase in natural satellites brings the total number of their Jovian moons to 79, more than those that are known to surround any other planet in our cosmic neighborhood.
Astronomers have discovered twelve new moons orbiting Jupiter, bringing the total number of Jovian moons to 79. Photograph: Carnegie Institution for Science
Nine of the new moons discovered belong to an external group that orbits Jupiter in retrograde , which means that they travel in the opposite direction of the planet’s rotation. It is believed to be the remains of larger parental bodies that broke in collisions with asteroids, comets and other moons. Each one takes around two years to orbit the planet.
Two more of the moons are in a group that rotates much closer to the planet, in orbits that travel in the same direction as Jupiter’s rotational motion. Most likely they are pieces of a previously larger moon that broke in orbit, and their remains need almost a year to complete a turn around Jupiter. Which direction the moons circle around the planet depends on how they were first captured by Jupiter’s gravitational field.
Meanwhile, astronomers describe the twelfth new Jovian moon as an “oddball.” Less than a kilometer wide, the small body surrounds Jupiter in a prosperous orbit, but at a distance that means it crosses the path of other moons that rotate in the opposite direction. Scientists have named the new moon Valetudo, like the great-granddaughter of the Roman god Jupiter, the goddess of health and hygiene.
“This is an unstable situation,” said Sheppard. “Head-on collisions would quickly break apart and grind the objects down to dust.”
However, the scientist says that “collisions do not occur as often, every billion years or so,” reports The Guardian. “If one happens, we could detect it from Earth, but it is unlikely to happen soon,” the astronomer stated.
