(24835) 1995 SM 55
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Asteroid (24835) 1995 SM 55 |
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|---|---|
| Properties of the orbit ( animation ) | |
| Orbit type |
Cubewano or SDO Haumea family |
| Major semi-axis | 41,595 AU |
| eccentricity | 0.1 |
| Perihelion - aphelion | 37.423 AU - 45.767 AU |
| Inclination of the orbit plane | 27.1 ° |
| Length of the ascending node | 21.1 ° |
| Argument of the periapsis | 71.8 ° |
| Time of passage of the perihelion | January 2, 2040 |
| Sidereal period | 268 a 3.2 M |
| Mean orbital velocity | 4.61 km / s |
| Physical Properties | |
| Medium diameter | approx. 280 km 162 - 704 km |
| Albedo | 0.04-0.70 |
| Rotation period | 8.08 ± 0.03 h (0.3367 d ) |
| Absolute brightness | 4.3 - 4.9 mag |
| Spectral class | BV = 0.65 V-R = 0.37 |
| history | |
| Explorer | Nichole M. Danzl |
| Date of discovery | September 19, 1995 |
| Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . The affiliation to an asteroid family is automatically determined from the AstDyS-2 database . Please also note the note on asteroid items. | |
(24835) 1995 SM 55 is a Trans-Neptunian object that is classified as Cubewano or SDO . It is a member of the Haumea family.
discovery
(24835) 1995 SM 55 was discovered on September 19, 1995 by Nichole M. Danzl as part of the Spacewatch project at the Kitt Peak National Observatory near Tucson ( Arizona ). The discovery was announced on June 11, 1999. The IAU gave the planetoid the minor planet number 24835 .
After its discovery, SM 55 could be identified in photos from September 16, 1982 in 1995 and its observation period was extended by 13 years in order to calculate its orbit more precisely. Since then, SM 55 has been observed with earth-based telescopes in 1995 . In April 2017, there were a total of 174 observations over a period of 35 years.
properties
Orbit
(24835) 1995 SM 55 orbits the sun in 268.27 years on a slightly elliptical orbit between 37.42 AU and 45.77 AU from its center. The orbit eccentricity is 0.100, the orbit is 27.07 ° inclined to the ecliptic . The asteroid will reach its perihelion in 2040; The last perihelion should therefore have taken place around 1771. In 1995 the MPC classified the SM 55 as a Cubewano , while Marc Buie ( DES ) classified it as an SDO.
The asteroid is a member of the Haumea family, which consists of fragments from a previous collision on the dwarf planet Haumea .
size
There is still some uncertainty about the dimensions and reflectivity of the 1995 SM 55 ; the estimates vary from 162 to 704 km. In general, a diameter of around 500 to 600 km is assumed. The lowest value of 162 km comes from Mike Brown and is based on an assumed very high albedo of 70% and an absolute brightness of 5.0 m . Other values are based on lower albedo values of 4 to 7% typical for KBO and absolute brightnesses of 4.3 to 4.6 m . The most recent estimate assumes that the size of 1995 SM 55 does not exceed 280 km.
It is therefore uncertain whether 1995 SM 55 is in hydrostatic equilibrium and whether the asteroid is one of the dwarf planet candidates . Mike Brown believes that it is in 1995 SM 55 to perhaps no concerns dwarf planet. Gonzalo Tancredi rejects classification as a dwarf planet.
1995 SM 55 rotates once around its axis in 8 hours and 4.8 minutes. From this it follows that in a 1995 SM 55 year it performs 291,045.3 self- rotations (“days”).
| year | Dimensions km | source |
|---|---|---|
| 2005 | ≤704.0 | Grundy et al. a. |
| 2010 | 461.0 | Tancredi |
| 2016 | 519.43 | LightCurve DataBase |
| 2018 | 701.0 | Johnston |
| 2018 | <280.0 | Vilenius et al. a. |
| 2018 | 162.0 | Brown |
| The most precise determination is marked in bold . | ||
See also
- List of asteroids
- List of trans-Neptunian objects
- List of dwarf planets of the solar system
- List of moons from asteroids
Individual evidence
- ↑ MPC : MPEC 1999-L24: 1995 SM55, 1995 TL8, 1996 GQ21 (June 1999)
- ↑ MPC : (24835) = 1995 SM55 (September 2018)
- ↑ MPC : MPEC 2009-R09: Distant Minor Planets (September 2009)
- ↑ M. Buie et al. a .: Orbit Fit and Astrometric record for 24835 (January 2019)
- ^ A b G. Tancredi: Physical and dynamical characteristics of icy “dwarf planets” (plutoids) . IAU. April 1, 2010. Retrieved January 29, 2019.
- ↑ Grundy et al. a .: MPC: Diverse Albedos of Small Trans-Neptunian Objects
- ↑ AstSys: AstSys: LCDB Data for (24835)
- ↑ Johnston's Archives: List of Known Trans-Neptunian Objects (October 2018)
- ↑ E. Vilenius et al. a .: "TNOs are Cool": A survey of the trans-Neptunian region. XIV. Size / albedo characterization of the Haumea family observed with Herschel and Spitzer (October 2018)
- ↑ M. Brown : How many dwarf planets are there in the outer solar system? (November 2018)