CLOSING IN ON X

Discovery may bring new planet within reach

It’s a discovery that could make astronomers X-static.

Scientists may be one step closer to finding the long-rumored Planet X. A distant object with an orbit that’s far past Pluto has been spotted, the International Astronomical Union’s Minor Planet Center announced Tuesday.

The mystery object — called 2015 TG387 and nicknamed The Goblin — is about two-and-a-half times further away from the sun than Pluto is. Its distance is measured in astronomical units, or the distance between the Earth and sun. The Goblin is about 80 astronomical units from the sun, while Pluto is around 34 AU.

“We think there could be thousands of small bodies like 2015 TG387 out on the solar system’s fringes, but their distance makes finding them very difficult,” said David Tholen of the University of Hawaii, who aided in the discovery. “Currently we would only detect 2015 TG387 when it is near its closest approach to the sun. For some 99% of its 40,000-year orbit, it would be too faint to see.”

The object was discovered by the scientists while searching for dwarf planets and Planet X in what they’re calling the largest survey of the distant solar system to date.

“These distant objects are like breadcrumbs leading us to Planet X,” said astronomer Scott Sheppard of the Carnegie Institution for Science. “The more of them we can find, the better we can understand the outer solar system and the possible planet that we think is shaping their orbits — a discovery that would redefine our knowledge of the solar system’s evolution.”

The team first noticed 2015 TG387 in October of 2015 from a Japanese telescope on top of Mauna Kea, a dormant volcano in Hawaii. But it took them a few years to figure out the orbit for the object since it moves so slowly. Later sightings from Carnegie’s Las Campanas Observatory in Chile and the Discovery Channel Telescope in Arizona in 2015 through this year helped determine The Goblin’s orbit.