Discovery [1] | |
---|---|
Discovered by | E. Johnson |
Discovery site | Johannesburg Obs. |
Discovery date | 25 April 1949 |
Designations | |
(1922) Zulu | |
Named after | Zulu (tribe) [2] |
1949 HC | |
main-belt ·(outer) [1] [3] 2:1 res [4] | |
Orbital characteristics [1] | |
Epoch 16 February 2017 (JD 2457800.5) | |
Uncertainty parameter 0 | |
Observation arc | 67.70 yr (24,727 days) |
Aphelion | 4.7945 AU |
Perihelion | 1.6775 AU |
3.2360 AU | |
Eccentricity | 0.4816 |
5.82 yr (2,126 days) | |
187.91° | |
0° 10m 9.48s / day | |
Inclination | 35.446° |
226.53° | |
31.395° | |
Earth MOID | 0.7153 AU |
Jupiter MOID | 0.6296 AU |
Physical characteristics | |
Dimensions | 12.41±2.60 km [5] 19.30 km (calculated) [3] 20.561±0.321 km [6] [7] |
18.64±0.01 h [8] 18.65 h [9] | |
0.055±0.006 [6] [7] 0.057 (assumed) [3] 0.16±0.05 [5] | |
C [3] | |
12.2 [6] ·12.27±0.24 [10] ·12.3 [1] [3] [5] | |
1922 Zulu, provisional designation 1949 HC, is a carbonaceous asteroid in a strongly unstable resonance with Jupiter, located in the outermost regions of the asteroid belt, and approximately 20 kilometers in diameter. It was discovered on 25 April 1949, by South African astronomer Ernest Johnson at Union Observatory in Johannesburg, and named for the South African Zulu people. [2] [11]
Zulu is one of few strongly unstable asteroids located near the 2:1 orbital resonance with the gas giant Jupiter, that corresponds to one of the prominent Kirkwood gaps in the asteroid belt. [4]
It orbits the Sun at a distance of 1.7–4.8 AU once every 5 years and 10 months (2,126 days). Its orbit has an eccentricity of 0.48 and an inclination of 35° with respect to the ecliptic. [1] The body's observation arc begins with its official discovery observation at Johannesburg, as no precoveries were taken and no prior identifications were made. [11]
Zulu was lost shortly after its 1949-discovery (see Lost asteroid), and only rediscovered in 1974 by Richard Eugene McCrosky, Cheng-yuan Shao and JH Bulger based on a predicted position by C. M. Bardwell of the Cincinnati Observatory. [12] It is quite highly inclined for asteroids in the asteroid belt, with an inclination of 35.4 degrees. This may be related to its 2:1 resonance with Jupiter.
In May 2002, a rotational lightcurve of Zulu was obtained from photometric observations by American astronomer Robert Stephens at the Santana Observatory in California. Lightcurve analysis gave a well-defined rotation period of 18.64 hours with a brightness variation of 0.11 magnitude ( U=3 ). [8] One month later, French amateur astronomers René Roy and Laurent Brunetto obtained another lightcurve with a concurring period of 18.65 hours and an amplitude of 0.09 magnitude ( U=1 ). [9]
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Zulu measures 12.41 and 20.561 kilometers in diameter and its surface has an albedo of 0.055 and 0.16. [5] [6] [7] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for a carbonaceous C-type asteroid of 0.057 and calculates a diameter of 19.30 kilometers with an absolute magnitude of 12.3. [3]
This minor planet was named after the South African Zulu people, in recognition of the tribesmen who devotedly worked at the Johannesburg Union Observatory. The name also closely relates to 1362 Griqua and 1921 Pala, which also received tribal names and librate in the 2:1 ratio of Jupiter's mean motion as well. [2] The official naming citation was published by the Minor Planet Center on 20 February 1976 ( M.P.C. 3938). [13]
6433 Enya, provisional designation 1978 WC, is a stony background asteroid from the inner regions of the asteroid belt, approximately 7 kilometers in diameter. It was discovered on 18 November 1978, by Czech astronomer Antonín Mrkos at the Kleť Observatory in the Czech Republic. It was named for Irish musician Enya.
7317 Cabot, provisional designation 1940 ED, is a background asteroid in a resonance with Jupiter, located the inner regions of the asteroid belt, approximately 3.6 kilometers in diameter. It was discovered on 12 March 1940, by Hungarian astronomer György Kulin at the Konkoly Observatory in Budapest. The presumed S-type asteroid has a rotation period of 2.2 hours. It was named after Italian explorer John Cabot.
2751 Campbell, provisional designation 1962 RP, is a stony Nysian asteroid from the inner regions of the asteroid belt, approximately 6 kilometers in diameter.
(9928) 1981 WE9, provisional designation 1981 WE9, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 3 kilometers in diameter. It was discovered on 16 November 1981, by astronomers at Perth Observatory in Bickley, Australia.
10247 Amphiaraos is Jupiter trojan from the Greek camp, approximately 27 kilometers in diameter. It was discovered on 24 September 1960, by Dutch astronomers Ingrid and Cornelis van Houten at Leiden, and Tom Gehrels at the Palomar Observatory in California. The X/D-type asteroid has a long rotation period of 34.26 hours and possibly an elongated shape. It was named after the seer Amphiaraus (Amphiaraos) from Greek mythology.
1246 Chaka, provisional designation 1932 OA, is a background asteroid from the central regions of the asteroid belt, approximately 18 kilometers in diameter. It was discovered on 23 July 1932, by South African astronomer Cyril Jackson at the Union Observatory in Johannesburg. The uncommon A/Sl-type asteroid has a longer than average rotation period of 25.5 hours. It was named for the Zulu King Shaka.
1707 Chantal, provisional designation 1932 RL, is a stony background asteroid from the Florian region in the inner asteroid belt, approximately 7.5 kilometers in diameter. It was discovered on 8 September 1932, by astronomer Eugène Delporte at the Royal Observatory of Belgium in Uccle. The S-type asteroid has a rotation period of at least 10 hours. It was named for Chantal, the niece of Belgian astronomer Georges Roland.
1555 Dejan, provisional designation 1941 SA, is an asteroid from the background population of the central regions of the asteroid belt, approximately 22 kilometers in diameter. It was discovered on 15 September 1941, by Belgian astronomer Fernand Rigaux at the Royal Observatory of Belgium in Uccle. The asteroid was named after Dejan Đurković, son of Serbian astronomer Petar Đurković.
1267 Geertruida, provisional designation 1930 HD, is a carbonaceous background asteroid from the inner regions of the asteroid belt, approximately 20 kilometers in diameter. Discovered by astronomer Hendrik van Gent at Johannesburg Observatory in 1930, the asteroid was later named after Geertruid Pels, sister of Dutch astronomer Gerrit Pels.
2571 Geisei, provisional designation 1981 UC, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 6 kilometers in diameter. It was discovered by Japanese astronomer Tsutomu Seki at Geisei Observatory on 23 October 1981, and named for the Japanese village of Geisei.
1452 Hunnia, provisional designation 1938 DZ1, is a carbonaceous Meliboean asteroid from the outer regions of the asteroid belt, approximately 20 kilometers in diameter. It was discovered on 26 February 1938, by Hungarian astronomer György Kulin at the Konkoly Observatory in Budapest. The asteroid was named in honor of the Hungarian nation.
2043 Ortutay, provisional designation 1936 TH, is a dark asteroid from the outer regions of the asteroid belt, approximately 45 kilometers in diameter. The asteroid was discovered by Hungarian astronomer György Kulin at the Konkoly Observatory, Budapest, on 12 November 1936. It was named after Hungarian ethnographer Gyula Ortutay.
1512 Oulu, provisional designation 1939 FE, is a dark Hildian asteroid, slow rotator and possibly the largest known tumbler orbiting in the outermost region of the asteroid belt. With a diameter of approximately 80 kilometers, it belongs to the fifty largest asteroids in the outer main-belt. The body was discovered on 18 March 1939, by Finnish astronomer Heikki Alikoski at Turku Observatory in Southwest Finland and named for the Finnish town Oulu.
1405 Sibelius, provisional designation 1936 RE, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. It was discovered on 12 September 1936, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland. The asteroid was named after composer Jean Sibelius.
2169 Taiwan, provisional designation 1964 VP1, is a carbonaceous Astridian asteroid from the central regions of the asteroid belt, approximately 17 kilometers in diameter. It was discovered on 9 November 1964, by astronomers at the Purple Mountain Observatory near Nanking, China. It was named for Taiwan.
19848 Yeungchuchiu is a stony Eos asteroid from the outer region of the asteroid belt, approximately 12 kilometers in diameter. It was discovered on 2 October 2000 by Canadian amateur astronomer William Yeung at the Desert Beaver Observatory in Arizona, United States. It is the largest object found by the discoverer, just 1°.2 west of Jupiter, who named it after his father, Chu Chiu Yeung.
3823 Yorii, provisional designation 1988 EC1, is a carbonaceous asteroid from the outer region of the asteroid belt, approximately 11 kilometers in diameter.
10208 Germanicus, provisional designation 1997 QN1, is a stony Florian asteroid and binary system from the inner regions of the asteroid belt, approximately 3.5 kilometers in diameter.
31179 Gongju (provisional designation 1997 YR2) is a stony Nysian asteroid from the inner regions of the asteroid belt, approximately 5 kilometers (3 miles) in diameter. It was discovered on 21 December 1997, by Japanese amateur astronomer Naoto Sato at his Chichibu Observatory near Tokyo, central Japan. The S-type asteroid has a rotation period of 4.8 hours and possibly an elongated shape. It was named for the South Korean city of Gongju.
31249 Renéefleming (provisional designation 1998 DF14) is a dark Zhongguo asteroid from the outermost region of the asteroid belt, approximately 7 kilometers (4 miles) in diameter. It was discovered on 27 February 1998, by astronomers with the ODAS survey conducted at the CERGA Observatory near Caussols, France. The presumed C-type asteroid has a short rotation period of 3.34 hours. It was named for American soprano Renée Fleming.