Astronomy:2324 Janice

From HandWiki
Revision as of 07:56, 6 February 2024 by Jport (talk | contribs) (change)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Short description: Dark background asteroid from the outer regions of the asteroid belt
2324 Janice
Discovery [1]
Discovered byE. F. Helin
S. J. Bus
Discovery sitePalomar Obs.
Discovery date7 November 1978
Designations
(2324) Janice
Named afterJanice Cline [1]
(Supporter at Caltech)
1978 VS4 · 1929 WH
1934 VR · 1949 ME
1961 UP · 1971 OC1
1975 EM2 · 1977 RY4
A911 MC
Minor planet categorymain-belt [1][2] · (outer)
background[3] · Themis[4][5]
Orbital characteristics[2]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc83.28 yr (30,418 d)
|{{{apsis}}}|helion}}3.6382 AU
|{{{apsis}}}|helion}}2.5282 AU
3.0832 AU
Eccentricity0.1800
Orbital period5.41 yr (1,977 d)
Mean anomaly245.72°
Mean motion0° 10m 55.56s / day
Inclination0.3995°
Longitude of ascending node315.66°
305.63°
Physical characteristics
Mean diameter23.55 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]
Rotation period23.2±0.1 h[11]
Geometric albedo0.038±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]
Absolute magnitude (H)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]

Orbit and classification

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]

Physical characteristics

Janice is a presumed carbonaceous C-type asteroid which is the overall spectral type of members of the Themis family (602).[4]

Rotation period

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 ({{{1}}}).[11] As of 2018, no secure period has been obtained.[4]

Diameter and albedo

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]

Naming

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]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 "2324 Janice (1978 VS4)". Minor Planet Center. https://www.minorplanetcenter.net/db_search/show_object?object_id=2324. 
  2. 2.0 2.1 2.2 2.3 "JPL Small-Body Database Browser: 2324 Janice (1978 VS4)". Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2002324. 
  3. 3.0 3.1 "Small Bodies Data Ferret". Nesvorny HCM Asteroid Families V3.0. https://sbntools.psi.edu/ferret/PropertySearch/familyForm.action. 
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 "LCDB Data for (2324) Janice". Asteroid Lightcurve Database (LCDB). http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=2324%7CJanice. 
  5. 5.0 5.1 "Asteroid 2324 Janice – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. https://newton.spacedys.com/astdys/index.php?pc=1.1.6&n=2324. 
  6. 6.0 6.1 6.2 6.3 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. doi:10.3847/0004-6256/152/3/63. Bibcode2016AJ....152...63N. 
  7. 7.0 7.1 7.2 7.3 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. doi:10.1093/pasj/63.5.1117. Bibcode2011PASJ...63.1117U.  (online, AcuA catalog p. 153)
  8. 8.0 8.1 8.2 8.3 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. doi:10.1088/0004-637X/814/2/117. Bibcode2015ApJ...814..117N. 
  9. 9.0 9.1 9.2 9.3 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. doi:10.1088/0004-637X/741/2/90. Bibcode2011ApJ...741...90M. 
  10. 10.0 10.1 10.2 Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J. et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal 741 (2): 20. doi:10.1088/0004-637X/741/2/68. Bibcode2011ApJ...741...68M. 
  11. 11.0 11.1 11.2 Gartrelle, Gordon M. (April 2012). "Lightcurve Results for Eleven Asteroids". The Minor Planet Bulletin 39 (2): 40–46. ISSN 1052-8091. Bibcode2012MPBu...39...40G. 
  12. 12.0 12.1 12.2 12.3 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. doi:10.1088/2041-8205/759/1/L8. Bibcode2012ApJ...759L...8M. 
  13. 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. doi:10.1016/j.icarus.2015.08.007. Bibcode2015Icar..261...34V. 
  14. "MPC/MPO/MPS Archive". Minor Planet Center. https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html. 

External links