1191 Alfaterna

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1191 Alfaterna
Discovery [1]
Discovered byL. Volta
Discovery sitePino Torinese Obs.
Discovery date11 February 1931
MPC designation(1191) Alfaterna
Named after
Nuceria Alfaterna
(ancient Roman town)[2]
1931 CA · 1965 AA
main-belt · (outer)[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc85.79 yr (31,335 days)
Aphelion3.0286 AU
Perihelion2.7567 AU
2.8927 AU
4.92 yr (1,797 days)
0° 12m 1.08s / day
Physical characteristics
Dimensions38.92±13.94 km[4]
42.01 km (derived)[3]
42.09±3.0 km[5]
43.38±14.16 km[6]
46.11±0.63 km[7]
46.375±0.836 km[8]
47.397±0.175 km[9]
3.664 h (removed)[3][a]
33.12±1.92 (tentative)[10]
0.0479 (derived)[3]
10.60[5][7][8] · 10.77[6] · 10.8[1][3][4] · 10.89±0.21[11]

1191 Alfaterna, provisional designation 1931 CA, is a carbonaceous asteroid from the outer region of the asteroid belt, approximately 43 kilometers in diameter. It was discovered on 11 February 1931, by Italian astronomer Luigi Volta at the Observatory of Turin in northwestern Italy.[12] The asteroid was named for the ancient Roman town of Nuceria Alfaterna.[2]

Orbit and classification[edit]

Alfaterna orbits the Sun in the outer main-belt at a distance of 2.8–3.0 AU once every 4 years and 11 months (1,797 days). Its orbit has an eccentricity of 0.05 and an inclination of 18° with respect to the ecliptic.[1]

The first unused observation was taken at Heidelberg two nights prior to its discovery. The body's observation arc begins at Pino Torinese one week after its official discovery observation.[12]

Physical characteristics[edit]

Alfaterna has been characterized as a carbonaceous C-type asteroid.[3]

Rotation period[edit]

From 2005 to 2015, several astronomers such as Donald Pray, Henk de Groot and Raoul Behrend, Federico Manzini, as well as Laurent Bernasconi unsuccessfully tried to obtain a well-defined lightcurve of Alfaterna. While Pray derived a period of 3.664 hours with an amplitude of 0.05 magnitude (U=1),[a] the European astronomers published a tentative period of 33.12 hours (U=n.a.).[10] As of 2017, the body's spin rate effectively remains unknown.[3]

Diameter and albedo[edit]

According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Alfaterna measures between 38.92 and 47.397 kilometers in diameter and its surface has an albedo between 0.04 and 0.0574 (without preliminary results).[4][5][6][7][8][9] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0479 and a diameter of 42.01 kilometers using an absolute magnitude of 10.8.[3]


This minor planet is named for the ancient Roman town of "Nuceria Alfaterna", where now the town Nocera Inferiore/Superiore is located. The ancient city was founded between Pompeii and Salerno in 10th century BC. In 1957, the name was suggested by astronomer Alfonso Fresa at Turin Observatory.[2] The approved naming citation was published by the Minor Planet Center in the Minor Planet Circulars before November 1977 (M.P.C. 2882).[13]


  1. ^ a b Pray (2011) web: rotation period 3.664 hours with a brightness amplitude of 0.05 mag. Summary figures for (1191) Alfaterna at Collaborative Asteroid Lightcurve Link (CALL) had been removed; Period Flag "D" (no numerical value) and description "long?". A quality code of 1 was given.


  1. ^ a b c d "JPL Small-Body Database Browser: 1191 Alfaterna (1931 CA)" (2016-11-24 last obs.). Jet Propulsion Laboratory. Retrieved 26 July 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (1191) Alfaterna. Springer Berlin Heidelberg. p. 100. ISBN 978-3-540-00238-3. Retrieved 26 January 2017.
  3. ^ a b c d e f g h i "LCDB Data for (1191) Alfaterna". Asteroid Lightcurve Database (LCDB). Retrieved 26 January 2017.
  4. ^ a b c d 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. Retrieved 26 January 2017.
  5. ^ a b c d Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System. Bibcode:2004PDSS...12.....T. Retrieved 26 January 2017.
  6. ^ a b c d 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. Retrieved 26 January 2017.
  7. ^ a b c d 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. Retrieved 26 January 2017.
  8. ^ a b c d Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results" (PDF). The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 26 January 2017.
  9. ^ a b c 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. Retrieved 26 January 2017.
  10. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1191) Alfaterna". Geneva Observatory. Retrieved 26 January 2017.
  11. ^ 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. Retrieved 26 January 2017.
  12. ^ a b "1191 Alfaterna (1931 CA)". Minor Planet Center. Retrieved 26 January 2017.
  13. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 26 January 2017.

External links[edit]