‘Farout’ makes Pluto seem right next door

CAPE CANAVERAL, FLA. • Astronomers have spotted the farthest known object in our solar system — and they’ve nicknamed the pink cosmic body “Farout.”

The International Astronomical Union’s Minor Planet Center announced the discovery Monday.

“Farout” is about 120 astronomical units away — that’s 120 times the distance between Earth and the sun, or 17.7 billion kilometres. The previous record-holder was the dwarf planet Eris at 96 astronomical units.

Pluto, by comparison, is 34 astronomical units away.

The Carnegie Institution’s Scott Sheppard said the object is so far away and moving so slowly it will take a few years to determine its orbit. At that distance, it could take more than 1,000 years to orbit the sun.

Sheppard and his team spied the dwarf planet in November using a telescope in Hawaii. Their finding was confirmed by a telescope in Chile.

“I actually uttered ‘far out’ when I first found this object, because I immediately noticed from its slow movement that it must be far out there,” Sheppard wrote in an email. “It is the slowest-moving object I have ever seen and is really out there.”

It is an estimated 500 kilometres across and believed to be round. Its pink shade indicates an ice-rich object. Little else is known.

The discovery came about as the astronomers were searching for the hypothetical Planet X, a planet perhaps 10 times the size of Earth, believed by some to be orbiting the sun from vast distances, well beyond Pluto.

Astronomers will be watching Farout’s agonizingly slow orbit closely, because if it is warped or otherwise unusual, it helps them find Planet X, New Scientist magazine reported.

“It could further show that there is a planet out there, but that has to wait until we know the orbit,” Sheppard told the magazine. “But the orbit is likely over 1,000 years long, so it’s going to take several years of observations to really determine what it is.”

Sheppard was part of a three-person team who, just two months ago, discovered The Goblin, another distant and small object in our solar system, according to the website Universe Today.

Advances in telescopes planted on mountaintops in Hawaii and Chile are opening up new vistas in space.

“With new wide-field digital cameras on some of the world’s largest telescopes, we are finally exploring our Solar System’s fringes, far beyond Pluto,” said one of Sheppard’s colleagues, Northern Arizona University’s Chad Trujillo.