HONOLULU (NEXSTAR/KHON) — A research team at the University of Hawaii has confirmed that a recently discovered planetoid is almost four times farther from the sun than Pluto, making it the most distant object ever observed in our solar system.
The planetoid, nicknamed “Farfarout,” was first detected in 2018, the same year the previous record holder, “Farout,” was discovered. UH’s Institute for Astronomy says the team has now collected enough observations to pin down Farfarout’s orbit.
“The discovery of Farfarout shows our increasing ability to map the outer solar system and observe farther and farther towards the fringes of our solar system,” said Scott S. Sheppard, of the Carnegie Institution for Science. “Only with the advancements in the last few years of large digital cameras on very large telescopes has it been possible to efficiently discover very distant objects like Farfarout.”
The minor planet’s current distance from the sun is 132 astronomical units (au), compared with Pluto, which is only 34 au from the sun. A single astronomical unit is the mean distance between the Earth and the sun — approximately 93 million miles. That’s about eight light-minutes.
The planetoid has a very elongated orbit that takes it out to 175 au at its most distant and to around 27 au — inside Neptune’s orbit — when it’s closest to the sun.
“A single orbit of Farfarout around the Sun takes a millennium,” said David Tholen, of UH Mānoa. “Because of this long orbital period, it moves very slowly across the sky, requiring several years of observations to precisely determine its trajectory.”
Farfarout, which has been given the designation of 2018 AG37, will be given an official name after its orbit is better determined over the next few years.