645 Agrippina, provisional designation 1907 AG, is a stony asteroid from the outer region of the asteroid belt, roughly 30 kilometers in diameter. It was discovered by American astronomer reverend Joel Metcalf at Taunton, Massachusetts, USA, on 13 September 1907.[11]

645 Agrippina
Discovery [1]
Discovered byJ. H. Metcalf
Discovery siteTaunton, MA, United States
Discovery date13 September 1907
Designations
(645) Agrippina
Pronunciation/æɡrɪˈpnə/[2]
Named after
Agrippīna
(the Elder, the Younger)[3]
1907 AG
main-belt (outer)
Orbital characteristics[1]
Epoch 31 July 2016 (JD 2457600.5)
Uncertainty parameter 0
Observation arc108.28 yr (39551 d)
Aphelion3.6806 AU (550.61 Gm)
Perihelion2.7439 AU (410.48 Gm)
3.2123 AU (480.55 Gm)
Eccentricity0.14581
5.76 yr (2102.9 d)
322.43°
0° 10m 16.284s / day
Inclination7.0434°
0.16657°
84.246°
Earth MOID1.76975 AU (264.751 Gm)
Jupiter MOID1.61478 AU (241.568 Gm)
TJupiter3.163
Physical characteristics
Dimensions28.00±1.3 km (IRAS:17)[4]
30.86±0.76 km[5]
36.165±0.406 km[6]
29.57±0.58 km[7]
27.94 km (derived)[8]
Mean radius
14.00±0.65 km
32.6 h (1.36 d)[1][9]
34.39±0.05 h[10]
0.2381±0.025 (IRAS:17)[1][4]
0.198±0.011[5]
0.1369±0.0218[6]
0.213±0.028[7]
0.2283 (SIMPS)[8]
B–V = 0.871
U–B = 0.412
Tholen = S[1] · S[8]
9.94[1]

The S-type asteroid orbits the Sun at a distance of 2.7–3.7 AU once every 5 years and 9 months (2,103 days). Its orbit shows an eccentricity of 0.15 and is tilted by 7 degrees to the plane of the ecliptic. A photometric light-curve analysis from the 1980s and a provisional observation in 2004 rendered a rotation period of 32.6 and 34.4 hours, respectively.[9][10]

According to the surveys carried out by the Infrared Astronomical Satellite, IRAS, the Japanese Akari satellite, and the U.S.Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the asteroid has a dissimilar albedo in the range of 0.14 to 0.23, which leads to a varying estimate for its diameter from 28 to 36 kilometers.[4][5][6][7] The Collaborative Asteroid Lightcurve Link publishes an albedo of 0.23 from an alternative result of the Supplemental IRAS Minor Planet Survey (SIMPS) and derives a slightly lower diameter of 27.9 kilometers.[8]

The minor planet was named for two women of ancient Roman history. Agrippina the Elder (14 BCE – 33) was the daughter of the Roman statesman Marcus Vipsanius Agrippa, the wife of Germanicus and the mother of the Emperor Caligula. Her daughter, Agrippina the Younger (15–59 AD) was the mother of Emperor Nero. The naming might be influenced by the two letters of the provisional designation 1907 AG.[3] In the Dictionary of Minor Planet Names, Lutz Schmadel supposes that the name originated from a list of female names from mythology and history, compiled by the Astronomisches Rechen-Institut (ARI) in 1913. The ARI then sent this list to a number of astronomers with the request to name their discoveries in order to avoid confusion, as the number of unnamed minor planet up to number 700 had grown significantly at the time.[12]

References edit

  1. ^ a b c d e f "JPL Small-Body Database Browser: 645 Agrippina (1907 AG)" (2015-12-07 last obs.). Jet Propulsion Laboratory. Retrieved 7 May 2016.
  2. ^ Noah Webster (1884) A Practical Dictionary of the English Language
  3. ^ a b Schmadel, Lutz D. (2003). "(645) Agrippina". Dictionary of Minor Planet Names – (645) Agrippina. Springer Berlin Heidelberg. p. 64. doi:10.1007/978-3-540-29925-7_646. ISBN 978-3-540-29925-7.
  4. ^ a b c 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.
  5. ^ a b c 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)
  6. ^ a b c 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. Retrieved 5 January 2016.
  7. ^ a b c 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. Retrieved 5 January 2016.
  8. ^ a b c d "LCDB Data for (645) Agrippina". Asteroid Lightcurve Database (LCDB). Retrieved 5 January 2016.
  9. ^ a b 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 5 January 2016.
  10. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (645) Agrippina". Geneva Observatory. Retrieved 5 January 2016.
  11. ^ "645 Agrippina (1907 AG)". Minor Planet Center. Retrieved 5 January 2016.
  12. ^ Schmadel, Lutz D. (2003). "(579) Sidonia". Dictionary of Minor Planet Names – (579) Sidonia (Note about ARI). Springer Berlin Heidelberg. pp. 59–60. doi:10.1007/978-3-540-29925-7_580. ISBN 978-3-540-29925-7.

External links edit