Does our Solar System have 9 planets or only 8? Astronomers have gone back and forth on that a lot, with Pluto now being classified as a dwarf planet. However, out beyond Neptune there could be another elusive object orbiting the Sun and experts say they have the best evidence we’ve ever found for its existence.
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00:00Does our solar system have 9 planets or only 8?
00:07Astronomers have gone back and forth on that a lot, with Pluto now being classified as
00:11a dwarf planet.
00:12However, out beyond Neptune, there could be another elusive object orbiting the sun, and
00:17experts say they've found the strongest statistical evidence yet of its existence.
00:22Orbiters in the distant reaches of our system are called trans-Neptunian objects.
00:26Pluto is amongst them.
00:27Many are often overlooked by astronomers because of Neptune's mass and its gravitational
00:31impact on the objects around it.
00:33Neptune's mass impacts other nearby objects, making their orbits unstable and difficult
00:38to interpret.
00:39Because of this, a lot of data is overlooked, as it's too difficult to say for sure what's
00:43going on.
00:44But a new study has used computer simulations to suss it out, with the researchers writing
00:48in their paper, quote, accounting for observational biases, our results reveal that the orbital
00:53architecture of this group of objects aligns closely with the predictions of the P-9 inclusive
00:58model, with the researchers adding that the movements of these trans-Neptunian objects
01:02would be extremely unlikely without a ninth planet orbiting out there.
01:05Still, direct observations will need to be made, and that could be a long way off, as
01:09the hypothetical planet would be around 500 times the distance of the Earth to the Sun.