1014 Semphyra

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1014 Semphyra
Discovery [1]
Discovered byK. Reinmuth
Discovery siteHeidelberg Obs.
Discovery date29 January 1924
MPC designation(1014) Semphyra
Named after
figure in poem
by Aleksandr Pushkin[2]
1924 PW · 1932 WH
1984 YP6
main-belt · (middle)[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc93.02 yr (33,975 days)
Aphelion3.3624 AU
Perihelion2.2443 AU
2.8034 AU
4.69 yr (1,714 days)
0° 12m 36s / day
Physical characteristics
Dimensions14.89±3.58 km[4]
17.17±0.88 km[5]
17.487±0.250 km[6][7]
23.21 km (calculated)[3]
5.636±0.002 h[8]
0.057 (assumed)[3]
SMASS = Xe [1] · P[7] · X[3]
11.90[1][3][4] · 12.04±0.15[9] · 12.10[5][7]

1014 Semphyra, provisional designation 1924 PW, is a background asteroid from the central regions of the asteroid belt, approximately 17 kilometers in diameter. It was discovered on 29 January 1924, by German astronomer Karl Reinmuth at the Heidelberg Observatory in southwest Germany.[10] The asteroid was named after the character "Semphyra" in a poem by Aleksandr Pushkin.[2]

Orbit and classification[edit]

Semphyra has not been associated with any known asteroid family. It orbits the Sun in the central main belt at a distance of 2.2–3.4 AU once every 4 years and 8 months (1,714 days). Its orbit has an eccentricity of 0.20 and an inclination of 2° with respect to the ecliptic.[1]

The body's observation arc begins with its official discovery observation at Heidelberg.[10]

Physical characteristics[edit]

In the SMASS classification, Semphyra is an Xe-subtype that transitions from the X-type to the bright E-type asteroids, while the Wide-field Infrared Survey Explorer characterizes it as a dark P-type.[1][3][7]

Rotation period[edit]

In February 2004, a rotational lightcurve of Semphyra was obtained from photometric observations by American astronomer Donald Pray at the Carbuncle Hill Observatory, Rhode Island (I00). The observations were made at a low phase angle of 1.6–2.9°. Lightcurve analysis gave a well-defined rotation period of 5.636 hours with a brightness amplitude of 0.12 magnitude (U=3), indicating that the body has a rather spheroidal shape.[8]

Diameter and albedo[edit]

According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's WISE, Semphyra measures between 14.89 and 17.487 kilometers in diameter and its surface has an albedo between 0.083 and 0.12.[4][5][6][7]

The Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 23.21 kilometers based on an absolute magnitude of 11.9.[3]


This minor planet was named after the character "Semphyra" in a poem by Russian Aleksandr Pushkin (1799–1837), who was directly honored with the naming of (2208). The asteroid's official name was proposed by N. Komendantov (RI 740) and mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 97).[2]


  1. ^ a b c d e f "JPL Small-Body Database Browser: 1014 Semphyra (1924 PW)" (2017-02-04 last obs.). Jet Propulsion Laboratory. Retrieved 29 August 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). "(1014) Semphyra". Dictionary of Minor Planet Names – (1014) Semphyra. Springer Berlin Heidelberg. p. 87. doi:10.1007/978-3-540-29925-7_1015. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f g "LCDB Data for (1014) Semphyra". Asteroid Lightcurve Database (LCDB). Retrieved 29 August 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 29 August 2017.
  5. ^ 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 29 August 2017.
  6. ^ a b c 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. arXiv:1109.4096. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 29 August 2017.
  7. ^ a b c d e f 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.
  8. ^ a b Pray, Donald P. (March 2005). "Lightcurve analysis of asteroids 276, 539, 1014, 1067, 3693 and 4774". The Minor Planet Bulletin. 32 (1): 8–9. Bibcode:2005MPBu...32....8P. ISSN 1052-8091. Retrieved 29 August 2017.
  9. ^ 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 29 August 2017.
  10. ^ a b "1014 Semphyra (1924 PW)". Minor Planet Center. Retrieved 29 August 2017.

External links[edit]