The dwarf planet Haumea, which lies beyond the orbit of Neptune, in the Kuiper belt, surprises us again. Thanks to observations in which a dozen international telescopes have participated, a team of scientists led by José Luis Ortiz, from the Institute of Astrophysics of Andalusia (CSIC), has discovered that Haumea has a ring, like Saturn.
Haumea, named after the Hawaiian goddess of birth, is a rather unusual planet . It is classified as a dwarf planet, has a curious shape like a rugby ball or melon and has two moons. In addition, this dwarf planet, whose mass is one third that of Pluto, also has its own ring, probably made up of fragments of rock and ice.
Until now the existence of rings was only known on giant planets such as Saturn and Jupiter, but now we know that it is possible to find them on dwarf planets. It is the first discovery of a ring around a trans-Neptunian object.
“Until just a few years ago we only knew about the existence of rings around the giant planets (like Saturn) and, very recently, our team also discovered that two small bodies (Cariclo and Chiron) located between Jupiter and Neptune , belonging to the A family of objects called centaurs have dense rings, which was a great surprise, “Pablo Santos-Sanz, co-author of the work published in the journal Nature, explains to SINC.
“Now, in addition, we discover that bodies even more distant than centaurs, larger and with very different general characteristics, can also have rings”, highlights the researcher. In fact, it is the first discovery of a ring around a trans-Neptunian object, and shows that the presence of these gigantic ‘rings’ could be much more common than previously believed , both in our solar system and in other planetary systems ” , continues Santos-Sanz .
How did they discover the ring?
Taking advantage of a difficult moment to capture, in which Haumea eclipsed a distant star (URAT1 533-182543), researchers from the Institute of Astrophysics of Andalusia managed to determine the main characteristics of this body, discovering the surprising presence of a ring around it.
The ring in question is 2,287 kilometers from the center of the main body; it is darker than the surface of the dwarf planet itself and is about 70 kilometers thick.
The origin of this ring is unknown, but experts believe that it was able to tear minerals from its surface and that a part of them could be in orbit around this world forming the newly discovered ring.
Haumea is located about 8,000 million kilometers from the Sun (50 times farther than Earth from the Sun); It rotates rapidly on its own axis, since its rotation speed is 3.9 hours, much faster than any other body over 100 kilometers in the entire solar system. It takes 285 years to surround the Sun, hence its surface is covered in a very bright layer of ice. And, unlike other dwarf planets like Pluto, it has no atmosphere.
Reference: The size, shape, density and ring of the dwarf planet Haumea from a stellar occultation, Nature (2017). nature.com/articles/doi:10.1038/nature24051
