 1995 TL8 and its satellite (unresolved) imaged by theHubble Space Telescope | |
| Discovery[1][2] | |
|---|---|
| Discovered by | A. Gleason(Spacewatch) |
| Discovery site | Kitt Peak National Obs. |
| Discovery date | 15 October 1995 |
| Designations | |
| (48639) 1995 TL8 | |
| 1995 TL8 | |
| TNO[1] · Other TNO[3] detached[4] · distant[2] | |
| Orbital characteristics[1] | |
| Epoch 17 December 2020 (JD 2459200.5) | |
| Uncertainty parameter 2 | |
| Observation arc | 25.26 yr (9,225 days) |
| Aphelion | 65.218AU |
| Perihelion | 39.937 AU |
| 52.578 AU | |
| Eccentricity | 0.2404 |
| 381.25yr (139,251 days) | |
| 46.972° | |
| 0° 0m 9.36s / day | |
| Inclination | 0.2499° |
| 260.007° | |
| 84.397° | |
| Knownsatellites | 1 (D: 80 km)[5] |
| Physical characteristics | |
| Dimensions | 176 km[5] 420.27 km(calculated)[6] 495 km(estimated)[7] |
| 0.07(estimated)[7] 0.10(assumed)[6] 0.369[5] | |
| RR[8] · C(assumed)[6] | |
| 4.667±0.091(R)[9] · 4.8[1][6] · 5.1[7] · 5.290±0.060[a] | |
(48639) 1995 TL8 is a binarytrans-Neptunian object from thescattered disc in the outermost regions of theSolar System. It was discovered byArianna Gleason in 1995 and measures approximately 176 kilometers in diameter. Its 80-kilometerminor-planet moon was discovered on 9 November 2002.[5]
1995 TL8 was discovered on 15 October 1995, by American astronomerArianna Gleason as part ofUA'sSpacewatch survey atKitt Peak National Observatory, near Tucson, Arizona.[2]
It was the first of the bodies presently classified as ascattered-disc object (SDO)[3][failed verification] to be discovered, preceding the SDO prototype(15874) 1996 TL66 by almost a year.[10]
A companion was discovered byDenise C. Stephens andKeith S. Noll, from observations with theHubble 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 420 kilometres (260 mi) to the primary at the time of discovery, with a possible orbital period of about half a day and an estimated diameter of 161 kilometres (100 mi).[5]
1995 TL8 is classified asdetached object (scattered–extended) by theDeep Ecliptic Survey, since its orbit appears to be beyond significant gravitationalinteractions withNeptune's current orbit.[4] However, if Neptunemigrated outward, there would have been a period when Neptune had a higher eccentricity.
Simulations made in 2007 show that1995 TL8 appears to have less than a 1% chance of being in a 3:7resonance with Neptune, but it doesexecute circulations near this resonance.[11]
Thisminor planet wasnumbered by theMinor Planet Center on 20 November 2002.[12] As of 2025, it has not beennamed.[2]
