In the search for an exo-planet outside our solar system that can explain the long elliptical orbits of the planets, many new discoveries have fallen onto the laps astronomers seeking to find the elusive “Planet X”. One of these is 2015 TG387, nicknamed “the Goblin” — a new dwarf planet in our solar system.

Only just wider than Ireland

The Goblin is only 300 KM – 186 miles across, making it only just wider than the Emerald Isle. A visitor from a debris-filled region of space called the Oort Cloud, the Goblin’s orbit is extraordinarily unique, and Scott Shephard, Chad Trujillo, and David Tholen, the discoverers of the dwarf planet, think it goes a long way in confirming the presence of a massive planetoid outside our solar system.

Next Big Future

This hypothetical planet, called Planet X or Planet 9, has been theorized since 2014 as the culprit behind the long elliptical orbits our planets take around the sun. The size of Planet X would have to be huge in order to pull planets like Neptune and Earth away from the gravitational coercion of the sun.

Around the world in 40,000 years

Astronomers measure distances within our solar system in Astronomical Units, (AU) the distance between Earth and the Sun. When the Goblin arrives at the closest point in its orbit, it sits around 65 AU, about twenty more than when Pluto is at the farthest point in its orbit.


However, when 2015 TG387 departs the 65 AU mark, it will be 40,000 years before it reaches that point again; as it will go until it reaches 2,300 AU before turning around again.

Following a trail

The Goblin is one of several what are known as extreme Trans-Neptunian objects, and being so far out in the cold and dark they can tell us a lot about what exists in the outer solar system.

Astronomy Now

Dr. Shephard, one of the authors of a paper describing the discovery of the Goblin, described them as “breadcrumbs leading us to Planet X,” and believes the more Trans-Neptunian objects they find, the clearer the trail will become.