1919 Clemence
| Discovery [1] | |
|---|---|
| Discovered by | J. Gibson C. U. Cesco |
| Discovery site | El Leoncito |
| Discovery date | 16 September 1971 |
| Designations | |
| (1919) Clemence | |
Named after | Gerald Clemence (astronomer)[2] |
| 1971 SA · 1970 EA1 1971 QZ | |
| main-belt · (inner)[1] Hungaria [3][4] | |
| Orbital characteristics [1] | |
| Epoch 16 February 2017 (JD 2457800.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 44.70 yr (16,326 days) |
| Aphelion | 2.1199 AU |
| Perihelion | 1.7519 AU |
| 1.9359 AU | |
| Eccentricity | 0.0950 |
| 2.69 yr (984 days) | |
| 213.21° | |
| 0° 21m 57.24s / day | |
| Inclination | 19.338° |
| 356.99° | |
| 99.939° | |
| Physical characteristics | |
| Dimensions | 3.238±0.015 km[5] 3.276±0.010[6] 4.95 km (calculated)[4] |
| 67.4±0.1 h[7] 68.5±0.1 h[8] | |
| 0.3 (assumed)[4] 0.686±0.108[6] 0.7103±0.0672[5] | |
| B–V = 0.750[1] U–B = 0.254[1] Tholen = X[1] X [4] · E [5] | |
| 13.45[1][4][5] | |
1919 Clemence, provisional designation 1971 SA, is a bright Hungaria asteroid and suspected tumbler from the inner regions of the asteroid belt, approximately 4 kilometers in diameter. It was discovered on 16 September 1971, by American astronomer James Gibson together with Argentine astronomer Carlos Cesco at the Yale-Columbia Southern Station at Leoncito Astronomical Complex in Argentina.[3] It is named after astronomer Gerald Clemence.[2]
Description
The bright E-type asteroid, classified as a X-type body on the Tholen taxonomic scheme, is a member of the Hungaria family, which form the innermost dense concentration of asteroids in the Solar System. It orbits the Sun at a distance of 1.8–2.1 AU once every 2 years and 8 months (984 days). Its orbit has an eccentricity of 0.10 and an inclination of 19° with respect to the ecliptic.[1]
Photometric measurements of this body by American astronomer Brian Warner made in 2005 at the U.S. Palmer Divide Observatory (PDO), Colorado, showed a revised rotational light-curve with a period of 67.4±0.1 hours and a brightness variation of 0.15 in magnitude (U=2).[7] Czech astronomer Petr Pravec from the Ondřejov Observatory believes this may be a tumbling asteroid, yet observations are not sufficient to determine a non-principal axis rotation.[8][9]
According to the surveys carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the asteroid measures 3.2 kilometers in diameter and its surface has an outstandingly high albedo of 0.71,[5] while the Collaborative Asteroid Lightcurve Link (CALL) assumes an albedo of 0.30 and calculates a somewhat larger diameter of 4.95 kilometers.[4]
It is named for American astronomer Gerald Maurice Clemence (1908–1974), first scientific director of the United States Naval Observatory and professor of astronomy at the Yale Observatory, known for his work on the theory of the motion of Mars and Mercury, on the system of astronomical constants, and other research in celestial mechanics. He served as president of the American Astronomical Society and of IAU.[2]
References
- ^ a b c d e f g h "JPL Small-Body Database Browser: 1919 Clemence (1971 SA)" (2016-05-28 last obs.). Jet Propulsion Laboratory. Retrieved 21 March 2017.
- ^ a b c Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (1919) Clemence. Springer Berlin Heidelberg. p. 154. ISBN 978-3-540-00238-3. Retrieved 19 April 2016.
- ^ a b "1919 Clemence (1971 SA)". Minor Planet Center. Retrieved 19 April 2016.
- ^ a b c d e f "LCDB Data for (1919) Clemence". Asteroid Lightcurve Database (LCDB). Retrieved 19 April 2016.
- ^ a b c d e Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 19 April 2016.
- ^ a b Masiero, Joseph R.; Grav, T.; Mainzer, A. K.; Nugent, C. R.; Bauer, J. M.; Stevenson, R.; et al. (August 2014). "Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos". The Astrophysical Journal. 791 (2): 11. arXiv:1406.6645. Bibcode:2014ApJ...791..121M. doi:10.1088/0004-637X/791/2/121. Retrieved 21 March 2017.
- ^ a b Warner, Brian D.; Stephens, Robert, D.; Harris, Alan W.; Pravec, Petr (October 2009). "A Re-examination of the Lightcurves for Seven Hungaria Asteroids". The Minor Planet Bulletin. 36 (4): 176–179. Bibcode:2009MPBu...36..176W. ISSN 1052-8091. Retrieved 19 April 2016.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ a b Warner, Brian D. (September 2005). "Asteroid lightcurve analysis at the Palmer Divide Observatory - winter 2004-2005". The Minor Planet Bulletin. 32 (3): 54–58. Bibcode:2005MPBu...32...54W. ISSN 1052-8091. Retrieved 19 April 2016.
- ^ Pravec, P.; Scheirich, P.; Durech, J.; Pollock, J.; Kusnirák, P.; Hornoch, K.; et al. (May 2014). "The tumbling spin state of (99942) Apophis". Icarus. 233: 48–60. Bibcode:2014Icar..233...48P. doi:10.1016/j.icarus.2014.01.026. Retrieved 19 April 2016.
External links
- The Palmer Divide Observatory: Tour given by Brian Warner on YouTube (time 4:03 min.)
- Lightcurve plot of 1919 Clemence, Palmer Divide Observatory, B. D. Warner (2005)
- Asteroid Lightcurve Database (LCDB), query form (info)
- Dictionary of Minor Planet Names, Google books
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
- 1919 Clemence at the JPL Small-Body Database
