1323 Tugela

1323 Tugela

Discovery[1]
Discovered by	C. Jackson
Discovery site	Johannesburg Obs.
Discovery date	19 May 1934
Designations
MPC designation	(1323) Tugela
Named after	Tugela River[2] (South African river)
Alternative designations	1934 LD · 1974 HR3 1974 KM · 1974 KO A908 UB · A911 HC
Minor planet category	main-belt · (outer)[1][3] background[4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	109.02 yr (39,818 days)
Aphelion	3.7100 AU
Perihelion	2.7510 AU
Semi-major axis	3.2305 AU
Eccentricity	0.1484
Orbital period (sidereal)	5.81 yr (2,121 days)
Mean anomaly	234.50°
Mean motion	0° 10^m 10.92^s / day
Inclination	18.787°
Longitude of ascending node	45.241°
Argument of perihelion	136.10°
Physical characteristics
Dimensions	58.44±3.4 km[5] 58.50 km (derived)[3] 62.00±19.32 km[6] 63.45±0.94 km[7] 67.76±25.28 km[8] 78.295±0.511 km[9] 90.557±0.542 km[10] 110.11±1.73 km[11]
Synodic rotation period	19.50±0.02 h[12][a] 19.777±0.0365 h[13]
Geometric albedo	0.018±0.004[11] 0.0236±0.0044[10] 0.04±0.02[6] 0.04±0.03[8] 0.048±0.002[7] 0.0567±0.007[5] 0.0620 (derived)[3]
Spectral type	SMASS = Xc[1] P[10] · C (assumed)[3]
Absolute magnitude (H)	9.56±0.62[14] · 9.80[3][11] · 9.84[8] · 9.90[1][5][6][7][10] · 10.245±0.001 (S)[13]

1323 Tugela, provisional designation 1934 LD, is a dark background asteroid from the outer regions of the asteroid belt, approximately 60 kilometers in diameter. It was discovered on 19 May 1934, by South African astronomer Cyril Jackson at the Union Observatory in Johannesburg.[15] The asteroid was named for the Tugela River in western South Africa.[2]

Orbit and classification

Tugela is a non-family asteroid from the main belt's background population.[4] It orbits the Sun in the outer main-belt at a distance of 2.8–3.7 AU once every 5 years and 10 months (2,121 days; semi-major axis of 3.23 AU). Its orbit has an eccentricity of 0.15 and an inclination of 19° with respect to the ecliptic.[1]

The body's observation arc begins with its first identification as A908 UB at Heidelberg Observatory in October 1908, almost 26 years prior to its official discovery observation at Johannesburg.[15]

Physical characteristics

In the SMASS classification, Tugela is an Xc-subtype that transitions from the X-type to the carbonaceous C-type asteroids.[1] The Wide-field Infrared Survey Explorer (WISE) characterized it as a primitive P-type asteroid, while the Collaborative Asteroid Lightcurve Link (CALL) assumes it to be a C-type.[3][10]

Rotation period

Observations performed by American astronomer Brian Warner at the Palmer Divide Observatory in Colorado Springs, Colorado, during February 2007 produced a lightcurve with a period of 19.50 ± 0.02 hours and an amplitude of 0.25 ± 0.02 in magnitude (U=3).[12][a] In September 2011, photometry in the S-band at the Palomar Transient Factory gave a similar period of 19.777 hours with a brightness variation of 0.18 magnitude (U=2).[13]

Diameter and albedo

According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's WISE telescope, Tugela measures between 58.44 and 110.11 kilometers in diameter and its surface has an albedo between 0.018 and 0.0567.[5][6][7][8][9][10][11]

CALL largely agrees with IRAS and derives an albedo of 0.0620 with a diameter of 58.50 kilometers based on an absolute magnitude of 9.8.[3]

Naming

This minor planet was named after the Tugela River, the largest river in the KwaZulu-Natal Province of western South Africa. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 121).[2]

Notes

1. Lightcurve plot of 1323 Tugela, Palmer Divide Observatory, B. D. Warner (2007). Summary figures at the LCDB

References

1. "JPL Small-Body Database Browser: 1323 Tugela (1934 LD)" (2017-11-02 last obs.). Jet Propulsion Laboratory. Retrieved 30 November 2017.
2. Schmadel, Lutz D. (2007). "(1323) Tugela". Dictionary of Minor Planet Names – (1323) Tugela. Springer Berlin Heidelberg. p. 108. doi:10.1007/978-3-540-29925-7_1324. ISBN 978-3-540-00238-3.
3. "LCDB Data for (1323) Tugela". Asteroid Lightcurve Database (LCDB). Retrieved 30 November 2017.
4. "Asteroid 1323 Tugela – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 29 October 2019.
5. Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System. 12: IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 22 October 2019.
6. Nugent, C. R.; Mainzer, A.; Masiero, J.; Bauer, J.; Cutri, R. M.; Grav, T.; et al. (December 2015). "NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos". The Astrophysical Journal. 814 (2): 13. arXiv:1509.02522. Bibcode:2015ApJ...814..117N. doi:10.1088/0004-637X/814/2/117. S2CID 9341381. Retrieved 30 November 2017.
7. 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)
8. Nugent, C. R.; Mainzer, A.; Bauer, J.; Cutri, R. M.; Kramer, E. A.; Grav, T.; et al. (September 2016). "NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos". The Astronomical Journal. 152 (3): 12. arXiv:1606.08923. Bibcode:2016AJ....152...63N. doi:10.3847/0004-6256/152/3/63.
9. 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. S2CID 119293330.
10. 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. S2CID 35447010.
11. Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Nugent, C.; et al. (November 2012). "Preliminary Analysis of WISE/NEOWISE 3-Band Cryogenic and Post-cryogenic Observations of Main Belt Asteroids". The Astrophysical Journal Letters. 759 (1): 5. arXiv:1209.5794. Bibcode:2012ApJ...759L...8M. doi:10.1088/2041-8205/759/1/L8. S2CID 46350317. Retrieved 30 November 2017.
12. Warner, Brian D. (September 2007). "Asteroid Lightcurve Analysis at the Palmer Divide Observatory - December 2006 - March 2007". The Minor Planet Bulletin. 34 (3): 72–77. Bibcode:2007MPBu...34...72W. ISSN 1052-8091. Retrieved 30 November 2017.
13. 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. S2CID 8342929. Retrieved 30 November 2017.
14. Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. S2CID 53493339. Retrieved 30 November 2017.
15. "1323 Tugela (1934 LD)". Minor Planet Center. Retrieved 30 November 2017.

External links

• 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
• 1323 Tugela at AstDyS-2, Asteroids—Dynamic Site
  • Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
• 1323 Tugela at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit viewer · Orbit parameters · Physical parameters