“Planet Nine”, the Hypothetical Planet
Expansion of our horizons is upon us! Another planet, about 10 times the size of Earth has been discovered in our very own solar system, past the orbit of Neptune. Or has it?
“Planet Nine” is the name scientists have given to this theorized planet that, if it exists, lies about 20 times farther from the sun than Neptune does. That places it in the Kuiper Belt, a region of small, icy objects that includes Pluto, and its moon, Charon.
But hold the phone, because no planet has been discovered yet. In a video released by NASA, Jim Green, NASA’s director of planetary science, cautions that it is still too early to claim that Earth’s solar system again has nine planets (Sorry Pluto).
“The idea of a new planet is certainly an exciting one for me as a planetary scientist, and I think for all of us,” Green said in the video. “It is not, however, the detection of a new planet. It’s too early to say with certainty that there is a so-called ‘Planet X’ out there.”
The prediction of Planet Nine’s existence came from a paper released on Wednesday, January 20, 2016. This paper shows how the motion of some known bodies in the Kuiper Belt could be explained by the presence of a massive planet. Although this is far from a direct detection, and the prediction is based on solar system models that are built up and improved on using observational data, models do allows astronomers to look at what might exist beyond what has already been seen.
“The Jan. 20 paper in the Astronomical Journal is fueling our interest in planetary exploration, and fueling a debate that’s part of the scientific process,” Green said in the video. “It’s all about starting the process that could lead to an exciting result.”
Astronomers say that if this planet exists, it should be pretty easy to find with telescopes. A few months of scanning the sky in the region where the new planet is predicted to be might provide direct observational evidence of its existence, astronomers say.
But there is a possibility that Planet Nine doesn’t exist and that some other explanation accounts for the motion of objects that astronomers observe in the Kuiper Belt. Whatever the outcome, Green said, the general public will have “a front row seat” for the show.