The Outer Solar System Origins Survey captured images of RR245 last September.
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“There it was on the screen”, said Bannister, “this dot of light moving so slowly that it had to be at least twice as far as Neptune from the Sun”. (Pluto completes one lap around the sun every 248 Earth years.) You can see an animation of the new dwarf planet’s orbit here.
2015 RR245 is now on the way to its closest approach with the sun, bringing it about 3 billion miles from the star in 2096, according to the statement. The dwarf object has a strangely wide and elongated orbit around the Sun such that its farthest point is (apogee) is 120 times the distance between Earth and the Sun.
According to the International Astronomical Union, which decides such things, dwarf planets are celestial bodies that orbit the sun, are not moons, have enough mass to take on a almost round shape, and whose gravity has not cleared out the neighborhood around their orbits.
Gladman says that since most of the trans-Neptunian planets are incredibly faint and small, it is “exciting” to find a bright one that appears much easier to investigate and is located in an interesting orbit. Its precise orbit will be refined over the coming years, after which RR245 will be given a name.
New planetary monickers have to be approved by nomenclature panel in the International Astronomical Union (IAU). Objects as bright or brighter than RR245 are labeled.
Most dwarf planets were destroyed or ejected early in the solar system’s history when the gas giants migrated outward from the locations where they formed. The Kuiper Belt is home to thousands of much smaller trans-Neptunian worlds, the vast majority of which are still yet to discovered. Yet, knowing what’s going on with Pluto and Charon might not justify too specific a conclusion about this newly discovered dwarf planet. There are at least six other bodies that are a step away from being classified as dwarf planets and over 350 identified bodies that could fall under the same category sometime in the future.
Other dwarf planets in the Kuiper Belt region include Pluto, Eris, Haumea and Makemake.
“While not created to effectively detect dwarf planets, we’re delighted to have found one on such an interesting orbit”.
Either way, it is just large enough to be round, astronomers say, allowing it to be classified as a dwarf planet. It is one of the most remote known objects of its size in the solar system.
This animated image shows 2015 RR245’s slow motion across the sky over the course of three hours.
Hundreds of objects have been found up until now in the Kuiper Belt.
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But beyond helping us map the outer reaches of our Solar System, the discovery of these dwarf planets – and their unique geological composition – helps us understand more about the cosmic past in our corner of the galaxy.
