Scientists say they may have discovered the most distant known natural object in the Solar System, beaten only by the manmade Voyager and Pioneer spacecraft. At 103 times the Earth-Sun distance (103 AU, astronomical units), it would take the title from the current record holder, the dwarf planet Eris at 97 AU.
Dubbed V774104, the object was reported by astronomer Scott Sheppard of the Carnegie Institute of Washington at the American Astronomical Society’s Division for Planetary Sciences meeting in Maryland on November 10.
The mysterious object was found using the Subaru telescope in Mauna Kea, Hawaii, and is believed to be between 500 and 1,000 kilometers (310 and 620 miles) across. It appears to reside beyond even the Kuiper Belt, a ring of icy objects including comets at the edge of the Solar System, and could be on the edge of the next region, the Oort Cloud.
However, the exact orbital path of the object has not yet been determined. If its orbit is stable, then it remains interesting, but if it swings in much closer to the Sun, then the intrigue might be dampened. This is because it would mean it is likely not a resident of the interesting Oort Cloud region, but rather just a tourist passing through.
“We don’t know anything about its orbit,” said Scott Sheppard, reported in New Scientist. “We just know it’s the most distant object known.”
At 15.5 billion kilometers (9.6 billion miles) away from the Sun, the object is currently three times farther than the distance of Pluto. Scientists think there could be hundreds of objects of this size residing in the outer Solar System.
If V774104 is confirmed, though, it would join only two known objects in the Oort Cloud – the dwarf planet Sedna, which comes no closer to the Sun at 76 AU, and VP113, which comes within 80 AU.d