Discovery [1] | |
---|---|
Discovered by |
E. F. Helin S. J. Bus |
Discovery site | Palomar Obs. |
Discovery date | 7 November 1978 |
Designations | |
(2324) Janice | |
Named after | Janice Cline
[1] (Supporter at Caltech) |
1978 VS4 · 1929 WH 1934 VR · 1949 ME 1961 UP · 1971 OC1 1975 EM2 · 1977 RY4 A911 MC | |
main-belt
[1]
[2] · (
outer) background [3] · Themis [4] [5] | |
Orbital characteristics [2] | |
Epoch 23 March 2018 ( JD 2458200.5) | |
Uncertainty parameter 0 | |
Observation arc | 83.28 yr (30,418 d) |
Aphelion | 3.6382 AU |
Perihelion | 2.5282 AU |
3.0832 AU | |
Eccentricity | 0.1800 |
5.41 yr (1,977 d) | |
245.72 ° | |
0° 10m 55.56s / day | |
Inclination | 0.3995° |
315.66° | |
305.63° | |
Physical characteristics | |
Mean diameter | 23.55
km (calculated)
[4] 24.33±6.61 km [6] 24.44±1.22 km [7] 25.76±7.43 km [8] 28.463±0.354 km [9] 28.532±0.238 km [10] 28.9±15.91 km [11] 31.19±15.91 km [12] |
23.2±0.1 h [11] | |
0.038±0.004
[10] 0.050±0.040 [12] 0.06±0.04 [6] 0.0601±0.0049 [9] 0.07±0.03 [8] 0.08 (assumed) [4] 0.093±0.010 [7] | |
C (assumed) [4] | |
11.30
[7] · 11.40
[8]
[9]
[12] 11.46±0.36 [13] · 11.5 [2] [4] 11.68 [6] | |
2324 Janice, provisional designation 1978 VS4, is a dark background asteroid from the outer regions of the asteroid belt, approximately 25 kilometers (16 miles) in diameter. It was discovered on 7 November 1978, by American astronomers Eleanor Helin and Schelte Bus at the Palomar Observatory in California. [1] The asteroid was named for Janice Cline at Caltech. The presumably C-type asteroid has a rotation period of 23.2 hours. [4]
Based on osculating Keplerian orbital elements, Janice is located in the region of the Themis family ( 602), a very large family of carbonaceous asteroids, named after 24 Themis. [4]
When applying the hierarchical clustering method to its proper orbital elements, the object is both a non- family asteroid of the main belt's background population (according to Nesvorný), [3] as well as a core member of the Themis family (according to Milani and Knežević). [5]
It orbits the Sun in the outer main-belt at a distance of 2.5–3.6 AU once every 5 years and 5 months (1,977 days; semi-major axis of 3.08 AU). Its orbit has an eccentricity of 0.18 and an inclination of 0 ° with respect to the ecliptic. [2] The body's observation arc begins with its first observation as A911 MC at Lowell Observatory in June 1911, more than 67 years prior to its official discovery observation at Palomar. [1]
Janice is a presumed carbonaceous C-type asteroid which is the overall spectral type of members of the Themis family ( 602). [4]
In October 2010, a rotational lightcurve of Janice was obtained from photometric observations by Gordon Gartrelle at the University of North Dakota Observatory in Grand Forks ( 730). Lightcurve analysis gave a tentative rotation period of 23.2 hours with a brightness amplitude of 0.19 magnitude ( U=2-). [11] As of 2018, no secure period has been obtained. [4]
According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Janice measures between 24.33 and 31.19 kilometers in diameter and its surface has an albedo between 0.038 and 0.093. [6] [7] [8] [9] [10] [12]
The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.08 and calculates a diameter of 23.55 kilometers based on an absolute magnitude of 11.5. [4]
This minor planet was named after Janice Cline, who for many years has encouraged astrometric studies of minor planets at Caltech. [1] The official naming citation was published by the Minor Planet Center on 1 March 1981 ( M.P.C. 5850). [14]