Evidence of a Ninth Planet Found in Outer Solar System
Caltech researchers have found evidence of a giant planet tracing a bizarre, highly elongated orbit in the outer solar system. The object, which the researchers have nicknamed Planet Nine, has a mass about ten times that of Earth and orbits about 20 times farther from the sun on average than does Neptune (which orbits the sun at an average distance of 2.8 billion miles). It would take this new planet between 10,000 and 20,000 years to make just one full orbit around the sun. The researchers discovered the planet's existence through mathematical modeling and computer simulations but have not yet observed the object directly.
Transcript
00:00:00 What we have discovered is that numerous features of the Kuiper Belt, a field of icy debris beyond the orbit of Neptune, can be understood if the solar system possesses an additional ninth planet that resides well beyond the orbits of the known planets. When we looked at the outer solar system we realized that while most of the very distant objects, these objects beyond Neptune, beyond Pluto. Most of these objects, they all go around the sun and they're all sort of pointing off in all different directions, but the most distant objects all swing out in one direction in a very strange way that shouldn't happen. And we realized that the only way we can get them to all swing in one direction is if there is a massive planet, also very distant in the solar system, keeping them
00:00:52 in place while they all go around the sun. And we started looking at this and thinking this must be either a coincidence or it's caused by something else. It can't be caused by a planet because that's crazy. There are no planets out there. I went from trying very hard to be skeptical that what we were talking about was true to suddenly thinking, oh, this actually might even be true. So the object itself likely is more massive than the Earth, probably a little bit less massive than Neptune. It sits right in between that terrestrial to giant icy planet range. Its orbit, unlike the orbits of the known planets, is not nearly circular and planar. Instead, it is exceptionally wide, twenty times bigger than the orbit of Neptune. The orbital period of the Earth is, of course, one year.
00:01:42 The orbital period of Jupiter, the big player in our solar system, is about 10 years. The orbital period of this putative ninth planet, is twenty thousand years. We have nothing like it in the solar system, so it's new for us. It is, however, the most common mass of planets that have been found around all of the other stars. People have always looked at all these other planets in this strange mass range and said, "Wow, I wonder what these are I don't know what these are because we don't have anything like it in the solar system." Looks like maybe we do. There are many telescopes on the Earth that actually have a chance of being able to find it, and I think that many people will be inspired to use their telescopes.
00:02:24 I'm really hoping that as we announced this people will start a worldwide search to go find this ninth planet. History shows us that it's a bad idea to consistently say, "We have now reached the end of the solar system, and there's nothing beyond what we already know." And all those people who are mad that Pluto was no longer planet can be thrilled to know that there's a real planet out there still to be found.