1999 LE31
1999 LE31 is a centaur and damocloid on a retrograde and eccentric orbit from the outer region of the Solar System. It was first observed on 12 June 1999, by astronomers with the LINEAR program at the Lincoln Lab's ETS near Socorro, New Mexico, in the United States.[1] The unusual object measures approximately 16.8 kilometers (10 miles) in diameter.[2][3]
 Orbital diagram of the orbit of 1999 LE31 | |
| Discovery [1] | |
|---|---|
| Discovered by | LINEAR |
| Discovery site | Lincoln Lab ETS |
| Discovery date | 12 June 1999 (first observed only) |
| Designations | |
| 1999 LE31 | |
| centaur [2] · damocloid [3] unusual [4] · distant [1] | |
| Orbital characteristics [2] | |
| Epoch 27 April 2019 (JD 2458600.5) | |
| Uncertainty parameter 2 | |
| Observation arc | 19.23 yr (7,022 d) |
| Aphelion | 11.913 AU |
| Perihelion | 4.3396 AU |
| 8.1265 AU | |
| Eccentricity | 0.4660 |
| 23.17 yr (8,462 d) | |
| 316.77° | |
| 0° 2m 33s / day | |
| Inclination | 151.81° |
| 292.12° | |
| 32.319° | |
| Jupiter MOID | 0.517 AU |
| TJupiter | -1.3090 |
| Physical characteristics | |
Mean diameter | 16.8±4.2 km[2][3] |
| 0.056±0.026[2][3] | |
| B–R = 1.20[3] | |
| 12.5[1][2] | |
Description
1999 LE31 orbits the Sun at a distance of 4.3–11.9 AU once every 23 years and 2 months (8,462 days; semi-major axis of 8.13 AU). Its orbit has an eccentricity of 0.47 and an inclination of 152° with respect to the ecliptic.[2]
It spends most of its orbit located in the outer Solar System between Jupiter and Uranus,[5] and like all centaurs, has an unstable orbit caused by the gravitational influence of the giant planets. Due to this, it must have originated from elsewhere, most likely outside Neptune.[5] It is both a Jupiter and Saturn-crossing minor planet.[2] Of over half a million known minor planets, 1999 LE31 is one of about 60 that has a retrograde orbit.[6]
1999 LE31 is approximately 16.8 km in diameter.[2][3] It came to perihelion (closest approach to the Sun) in December 1998.[7] It was last observed in 2000, and will next come to perihelion in February 2022.[2]
Observations
This asteroid has been recorded at such observatories as:[1]
- Lincoln Laboratory (1.0-m f/2.15 reflector + CCD) - location of discovery
- Dominion Astrophysical Observatory (1.82-m reflector + CCD)
- Dynic Astronomical Observatory (0.60-m f/3.7 reflector + CCD)
- European Northern Observatory (1.0-m reflector + CCD)
- Farpoint (0.30-m Schmidt-Cassegrain + CCD)
- Kleť Observatory (0.57-m f/5.2 reflector + CCD)
- McDonald Observatory (0.76-m reflector + CCD)
- Roque de los Muchachos Observatory (1.0-m reflector + CCD)
See also
- 20461 Dioretsa a.k.a. 1999 LD31
- 2000 DG8
- List of notable asteroids
References
- "1999 LE31". Minor Planet Center. Retrieved 20 November 2018.
- "JPL Small-Body Database Browser: (1999 LE31)" (2018-08-07 last obs.). Jet Propulsion Laboratory. Retrieved 20 November 2018.
- Johnston, Wm. Robert (7 October 2018). "List of Known Trans-Neptunian Objects". Johnston's Archive. Retrieved 19 November 2018.
- "List Of Other Unusual Objects". Minor Planet Center. 14 November 2018. Retrieved 19 November 2018.
- Horner, J.; Evans, N. W.; Bailey, M. E. (November 2004). "Simulations of the population of Centaurs – I. The bulk statistics". Monthly Notices of the Royal Astronomical Society. 354 (3): 798–810. arXiv:astro-ph/0407400. Bibcode:2004MNRAS.354..798H. doi:10.1111/j.1365-2966.2004.08240.x. S2CID 16002759.
- "JPL Small-Body Database Search Engine: Asteroids and i > 90 (deg)". JPL Solar System Dynamics. Retrieved 15 November 2014.
- Seiichi Yoshida (3 July 2010). "1999 LE31". Seiichi Yoshida's Comet Catalog. Retrieved 15 November 2014.
External links
- MPEC 1999-M29 : 1999 LE31, Minor Planet Electronic Circular, Minor Planet Center
- Yanga R. Fernández, David C. Jewitt, and Scott S. Sheppard, Low Albedos Among Extinct Comet Candidates, May 22, 2001
- BAA Comet Section Comets of 1999, Ast.cam.ac.uk
- 1999 LE31 – Seiichi Yoshida @ aerith.net
- Asteroid 1999 LE31, Small Body Data Ferret
- 1999 LE31 at AstDyS-2, Asteroids—Dynamic Site
- 1999 LE31 at the JPL Small-Body Database
