A team of astronomers have confirmed the orbit of a distant asteroid at the farthest reaches of our solar system – appropriately nicknamed ‘Farfarout’.
The small planet, officially designated 2018 AG37, is nearly four times farther from the sun than Pluto. It is the most distant asteroid ever detected in our solar system, researchers announced this week.
Farfarout was first discovered in 2018, beating the previous record holder “Farout.” The team, responsible for both discoveries, has an ongoing survey on it outer solar system.
After being discovered at the Subary 8-meter telescope atop Maunakea in Hawaii, astronomers have used the Gemini North and Mageallan telescopes to track its orbit for the past few years. In a few years, when his job is continued, Farfarout will have an official name.
“Farfarout’s discovery demonstrates our increasing ability to map the outer solar system and observe further and further towards the edges of our solar system,” said Scott S. Sheppard, member of the discovery team. “Only with the advancements in recent years from large digital cameras to very large telescopes has it become possible to efficiently discover distant objects such as Farfarout.”
Farfarout’s mean distance from the sun is 132 astronomical units, which means that it is 132 times further from the sun than Earth. In comparison, Pluto is only 39 au from the sun.
NOIRLab / NSF / AURA / J. da Silva
Farfarout’s journey around the sun takes about 1,000 years. The asteroid, which is very faint, is estimated to be about 400 kilometers in diameter, on the smaller side dwarf planets like Pluto.
“A single orbit of Farfarout around the sun takes a millennium,” said David Tholen, member of the discovery team. “Because of this long orbit, it moves very slowly through the air, requiring years of observations to determine its orbit precisely.”
Interactions with Neptune are responsible for the asteroid’s large, elongated orbit. Its orbit reaches 175 au at its farthest distance and about 27 au, in the orbit of Neptune, when closest to the sun.
Neptune’s effects on Farfarout’s orbit also mean that the asteroid is unlikely to contribute to scientists’ efforts to find a mysterious unknown planet lurking in the outskirts of the solar system.
“Farfarout’s orbital dynamics may help us understand how Neptune formed and evolved, as Farfarout was likely thrown into the outer solar system by getting too close to Neptune in the distant past,” said Chad Trujillo, a member of the discovery team. “Farfarout will likely interact strongly with Neptune again as their orbits continue to intersect.”
Scientists think they will eventually find the hypothetical “Planet Nine. “
“Farfarout is just the tip of the iceberg of solar system objects in the distant solar system,” Sheppard said.