Astronomy:(508338) 2015 SO20
| Discovery[1][2][3] | |
|---|---|
| Discovered by | M. E. Schwamb |
| Discovery site | La Silla Obs. |
| Discovery date | 8 October 2010 |
| Designations | |
| (508338) 2015 SO20 | |
| 2015 SO20 · 2010 TF182 | |
| Minor planet category | TNO[1] · E-SDO[4] distant[2] · detached extreme |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 2 | |
| Observation arc | 6.96 yr (2,543 days) |
| |{{{apsis}}}|helion}} | 290.09 AU |
| |{{{apsis}}}|helion}} | 33.164 AU |
| 161.63 AU | |
| Eccentricity | 0.7948 |
| Orbital period | 2054.81 yr (750,519 d) |
| Mean anomaly | 0.0032° |
| Mean motion | 0° 0m 1.8s / day |
| Inclination | 23.451° |
| Longitude of ascending node | 33.619° |
| 354.80° | |
| Physical characteristics | |
| Dimensions | 221 km (calculated)[5] 222 km (calculated)[4] |
| Geometric albedo | 0.08 (assumed)[5] 0.09 (assumed)[4] |
| Absolute magnitude (H) | 6.5[1] · 6.7[5] |
(508338) 2015 SO20 is an extreme trans-Neptunian object and extended scattered disc object from the outermost region of the Solar System, approximately 220 kilometers (140 miles) in diameter.
Description
This minor planet was first observed as 2010 TF182 on 8 October 2010, by American astronomer Megan Schwamb at ESO's La Silla Observatory in northern Chile.[2] It has also been observed as 2015 SO20 during the Calar Alto TNO Survey (Z79) at the Calar Alto Observatory, Spain, on 20 September 2015.[3]
It orbits the Sun at a distance of 33.2–290.1 AU once every 2054 years and 9 months (semi-major axis of 161 AU). Its orbit has an eccentricity of 0.79 and an inclination of 23° with respect to the ecliptic.[1]
Extended scattered disc
It is one a small number of detached objects with perihelion distances of 30 AU or more, and semi-major axes of 150 AU or more.[6] Such objects can not reach such orbits without some perturbing object, which lead to the speculation of planet nine.
Physical characteristics
Based on an absolute magnitude of 6.5 and an assumed albedo of 0.09, the Johnston's Archive calculated a mean-diameter of 222 kilometers.[4] Michael Brown estimates an albedo of 0.08 with a diameter of 221 kilometers using an absolute magnitude of 6.7. He also considers it a dwarf-planet candidate with a low probability ("possible").[5]
See also
References
- ↑ 1.0 1.1 1.2 1.3 1.4 "JPL Small-Body Database Browser: 508338 (2015 SO20)". Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=3731294. Retrieved 14 October 2017.
- ↑ 2.0 2.1 2.2 "(508338) 2015 SO20". Minor Planet Center. https://www.minorplanetcenter.net/db_search/show_object?object_id=2015+SO20. Retrieved 14 October 2017.
- ↑ 3.0 3.1 "List Of Centaurs and Scattered-Disk Objects". Minor Planet Center. http://www.minorplanetcenter.org/iau/lists/Centaurs.html. Retrieved 14 October 2017.
- ↑ 4.0 4.1 4.2 4.3 "List of known Trans-Neptunian Objects". Johnston's Archive. http://www.johnstonsarchive.net/astro/tnoslist.html. Retrieved 14 October 2017.
- ↑ 5.0 5.1 5.2 5.3 Michael E. Brown. "How many dwarf planets are there in the outer solar system?". California Institute of Technology. http://web.gps.caltech.edu/~mbrown/dps.html. Retrieved 9 December 2017.
- ↑ minorplanetcenter.net: q>30, a>150
External links
- List Of Centaurs and Scattered-Disk Objects, Minor Planet Center
- List of known Trans-Neptunian Objects, Johnston's Archive
- Discovery Circumstances: Numbered Minor Planets (505001)-(510000) – Minor Planet Center
- (508338) 2015 SO20 at AstDyS-2, Asteroids—Dynamic Site
- (508338) 2015 SO20 at the JPL Small-Body Database
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