Looking for Planet 9: Researchers find new objects to aid search
Several never-before-seen objects with orbits around the Sun that are greater than Neptune's have been observed by researchers Scott Sheppard, of the Carnegie Institution for Science, and Chadwick Trujillo, of Northern Arizona University. These trans-Neptunian objects will likely assist the research team in identifying the size and distance from the Sun of a ninth planet, which would influence the movement and placements of the newly-observed objects nearby.
In 2014, Sheppard and Trujillo discovered an object — 2012 VP113, also known as "Biden" — considered to have the most-distant orbit in the entire Solar System. This finding led them to predict a ninth planet exists beyond Pluto, now classified as a dwarf planet.
Based on analysis of smaller nearby objects, the ninth planet, or Planet 9, could be located at more than 200 times Earth's distance from the Sun, with a mass ranging from as much as 15 times the size of Earth to the size of Neptune. Planet 9 is likely maneuvering the newfound objects into a similar orbit, they said.
"Objects found far beyond Neptune hold the key to unlocking our Solar System’s origins and evolution," Sheppard said in a news release. "Though we believe there are thousands of these small objects, we haven’t found very many of them yet, because they are so far away. The smaller objects can lead us to the much bigger planet we think exists out there. The more we discover, the better we will be able to understand what is going on in the outer Solar System."
The research pair have now reported the newfound objects, including the first Oort Cloud object found beyond Neptune, to the International Astronomical Union's Minor Planet Center to receive official designations.
Sheppard and Trujillo, along with the University of Hawaii's David Tholen, are using some of the most powerful telescopes and cameras available to analyze objects beyond Neptune, yet they have covered only about 10 percent of the area outside Neptune and the Kuiper Belt.
"Right now we are dealing with very low-number statistics, so we don’t really understand what is happening in the outer Solar System," Sheppard said. "Greater numbers of extreme trans-Neptunian objects must be found to fully determine the structure of our outer Solar System."
The research is funded by NASA, according to the news release.