(48639) 1995 TL8
is a binary trans-Neptunian object from the scattered disc in the outermost regions of the Solar System. It was discovered by Arianna Gleason in 1995 and measures approximately 176 kilometers in diameter. Its 80-kilometer minor-planet moon was discovered on 9 November 2002.
Discovery
was discovered on 15 October 1995, by American astronomer Arianna Gleason as part of UA's Spacewatch survey at Kitt Peak National Observatory, near Tucson, Arizona.It was the first of the bodies presently classified as a scattered-disc object to be discovered, preceding the SDO prototype by almost a year.
Satellite
A companion was discovered by Denise C. Stephens and Keith S. Noll, from observations with the Hubble Space Telescope taken on 9 November 2002, and announced on 5 October 2005. The satellite is relatively large, having a likely mass of about 10% of the primary. Its orbit has not been determined, but it was at a separation of only about to the primary at the time of discovery, with a possible orbital period of about half a day and an estimated diameter of.Scattered–extended object
is classified as detached object by the Deep Ecliptic Survey, since its orbit appears to be beyond significant gravitational interactions with Neptune's current orbit. However, if Neptune migrated outward, there would have been a period when Neptune had a higher eccentricity.Simulations made in 2007 show that appears to have less than a 1% chance of being in a 3:7 resonance with Neptune, but it does execute circulations near this resonance.