1305 Phongolo, provisional designation 1928 OC, is a background asteroid from the outer regions of the asteroid belt, approximately 25 kilometers in diameter. It was discovered on 19 July 1928, by English astronomer Harry Edwin Wood at the Union Observatory in Johannesburg, South Africa.[14] The asteroid was named for the South African Pongola River.[2]
| Discovery[1] | |
|---|---|
| Discovered by | H. E. Wood |
| Discovery site | Johannesburg Obs. |
| Discovery date | 19 July 1928 |
| Designations | |
| (1305) Phongola | |
Named after | Pongola River[2] (South Africa river) |
| 1928 OC · 1927 FD 1929 SQ · 1932 FA 1933 MB · 1979 NE | |
| main-belt · (outer)[3] background[4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 90.59 yr (33,087 days) |
| Aphelion | 3.2336 AU |
| Perihelion | 2.7909 AU |
| 3.0123 AU | |
| Eccentricity | 0.0735 |
| 5.23 yr (1,910 days) | |
| 89.261° | |
| 0° 11m 18.6s / day | |
| Inclination | 2.3174° |
| 62.956° | |
| 146.96° | |
| Physical characteristics | |
| Dimensions | 24.110±0.277 km[5] 25.12±0.91 km[6] 25.124±0.200 km[7] 41.45 km (derived)[3] |
| 8 h[8] 8.03 h[9] 8.0585±0.0003 h[10] 8.059±0.0015 h[11] 8.06±0.02 h[12] 8.335±0.002 h[13] | |
| 0.057 (assumed)[3] 0.157±0.012[6] 0.1576±0.0296[7] 0.169±0.038[5] | |
| C (suspected)[3][9] B–V = 0.700[1] | |
| 10.426±0.002 (R)[11] · 10.64[3][7][9] · 10.65[1][6] | |
Orbit and classification
editPhongolo is a non-family asteroid from the main belt's background population.[4] It orbits the Sun in the outer asteroid belt at a distance of 2.8–3.2 AU once every 5 years and 3 months (1,910 days; semi-major axis of 3.01 AU). Its orbit has an eccentricity of 0.07 and an inclination of 2° with respect to the ecliptic.[1]
The body's observation arc begins with its first observation as 1927 FD at Heidelberg Observatory in March 1927, or 16 months prior to its official discovery observation at Johannesburg.[14]
Physical characteristics
editPhongolo is a suspected carbonaceous C-type asteroid.[3][9] The space-based survey gave an albedo (see below) that is not in-line with a carbonaceous spectral type.[5][6][7]
Rotation period
editSeveral rotational lightcurve of Phongolo have been obtained from photometric observations since 1984.[8][9][10][11][12][13] Analysis of the best-rated lightcurve gave a rotation period of 8.335 hours and a consolidated brightness amplitude between 0.14 and 0.19 magnitude (U=3-).[3][13]
Diameter and albedo
editAccording to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Pongola measures between 24.110 and 25.124 kilometers in diameter and its surface has an albedo between 0.157 and 0.169.[5][6][7]
The Collaborative Asteroid Lightcurve Link assumes a much lower standard albedo for carbonaceous asteroids of 0.057 and consequently derives a much larger diameter of 41.45 kilometers based on an absolute magnitude of 10.64.[3]
Naming
editThis minor planet was named by the discoverer after the Phongolo River (Phongolo; Pongolarivier) in KwaZulu-Natal, South Africa. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 119).[2]
References
edit- ^ a b c d e "JPL Small-Body Database Browser: 1305 Pongola (1928 OC)" (2017-10-29 last obs.). Jet Propulsion Laboratory. Retrieved 19 December 2017.
- ^ a b c Schmadel, Lutz D. (2007). "(1305) Pongola". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 107. doi:10.1007/978-3-540-29925-7_1306. ISBN 978-3-540-00238-3.
- ^ a b c d e f g h "LCDB Data for (1305) Pongola". Asteroid Lightcurve Database (LCDB). Retrieved 19 December 2017.
- ^ a b "Asteroid 1305 Pongola – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 29 October 2019.
- ^ a b c d 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.
- ^ a b c d e Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)
- ^ 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.
- ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1305) Pongola". Geneva Observatory. Retrieved 19 December 2017.
- ^ a b c d e Binzel, R. P. (October 1987). "A photoelectric survey of 130 asteroids". Icarus. 72 (1): 135–208. Bibcode:1987Icar...72..135B. doi:10.1016/0019-1035(87)90125-4. ISSN 0019-1035. Retrieved 19 December 2017.
- ^ a b Sada, Pedro V.; Olguin, Lorenzo; Saucedo, Julio C.; Loera-Gonzalez, Pablo; Cantu-Sanchez, Laura; Garza, Jaime R.; et al. (July 2017). "Results of the 2016 Mexican Asteroid Photometry Campaign". The Minor Planet Bulletin. 44 (3): 239–242. Bibcode:2017MPBu...44..239S. ISSN 1052-8091. Retrieved 19 December 2017.
- ^ a b c Waszczak, Adam; Chang, Chan-Kao; Ofek, Eran O.; Laher, Russ; Masci, Frank; Levitan, David; et al. (September 2015). "Asteroid Light Curves from the Palomar Transient Factory Survey: Rotation Periods and Phase Functions from Sparse Photometry". The Astronomical Journal. 150 (3): 35. arXiv:1504.04041. Bibcode:2015AJ....150...75W. doi:10.1088/0004-6256/150/3/75. Retrieved 19 December 2017.
- ^ a b Ditteon, Richard; Horn, Lauren; Kamperman, Amy; Vorjohan, Bradley; Kirkpatrick, Elaine (January 2012). "Asteroid Lightcurve Analysis at the Oakley Souther Sky Observatory: 2011 April-May". The Minor Planet Bulletin. 39 (1): 26–28. Bibcode:2012MPBu...39...26D. ISSN 1052-8091. Retrieved 19 December 2017.
- ^ a b c Mansego, Enrique Arce; Rodriguez, Pedro Brines; de Haro, Juan Lozano; Chiner, Onofre Rodrigo; Silva, Alvaro Fornas; Porta, David Herrero; et al. (October 2016). "Eighteen Asteroids Lightcurves at Asteroides Observers (OBAS) - MPPD: 2016 March-May". The Minor Planet Bulletin. 43 (4): 332–336. Bibcode:2016MPBu...43..332M. ISSN 1052-8091. Retrieved 19 December 2017.
- ^ a b "1305 Pongola (1928 OC)". Minor Planet Center. Retrieved 19 December 2017.
External links
edit- Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
- 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
- 1305 Pongola at AstDyS-2, Asteroids—Dynamic Site
- 1305 Pongola at the JPL Small-Body Database
