Langbahn Team – Weltmeisterschaft

1555 Dejan

1555 Dejan
Shape model of Dejan from its lightcurve
Discovery[1]
Discovered byF. Rigaux
Discovery siteUccle Obs.
Discovery date15 September 1941
Designations
(1555) Dejan
Named after
Dejan Đurković (son of astronomer Petar Đurković)[2]
1941 SA · 1932 PC
1934 CD1 · 1954 NJ
main-belt · (middle)[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc84.64 yr (30,913 days)
Aphelion3.4332 AU
Perihelion1.9442 AU
2.6887 AU
Eccentricity0.2769
4.41 yr (1,610 days)
71.768°
0° 13m 24.96s / day
Inclination6.0200°
318.08°
47.825°
Physical characteristics
Dimensions19.21 km (calculated)[3]
21.77±7.25 km[4]
23.199±0.314 km[5][6]
24.04±0.48 km[7]
16.960±0.002 h[8]
0.053±0.006[5]
0.0531±0.0056[6]
0.068±0.003[7]
0.08±0.09[4]
0.10 (assumed)[3][a]
S/C[3][a]
11.65[4] · 11.70[1][3][6][7]

1555 Dejan, provisional designation 1941 SA, is an asteroid from the background population of the central regions of the asteroid belt, approximately 22 kilometers in diameter. It was discovered on 15 September 1941, by Belgian astronomer Fernand Rigaux at the Royal Observatory of Belgium in Uccle.[9] The asteroid was named after Dejan Đurković, son of Serbian astronomer Petar Đurković.

Orbit and classification

Dejan is a non-family asteroid from the main belt's background population. It orbits the Sun in the central asteroid belt at a distance of 1.9–3.4 AU once every 4 years and 5 months (1,610 days). Its orbit has an eccentricity of 0.28 and an inclination of 6° with respect to the ecliptic.[1] The body's observation arc begins with its first identification as 1932 PC at Johannesburg Observatory in August 1932, more than 9 years prior to its official discovery observation at Uccle.[9]

Naming

This minor planet was named after Dejan Đurković, son of Petar Đurković (1908–1981), a Serbian astronomer and discoverer of minor planets at the Belgrade Observatory. The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 137).[2]

Physical characteristics

Rotation period

In September 2016, a rotational lightcurve of Dejan was obtained from photometric observations by the Spanish amateur astronomer group OBAS. Lightcurve analysis gave a rotation period of 16.960 hours with a brightness variation of 0.41 magnitude (U=2+).[8]

Diameter and albedo

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Dejan measures 21.77 and 23.199 kilometers in diameter and its surface has an albedo of 0.053 and 0.08, respectively,[4][5][6] while the Japanese Akari satellite found a diameter of 24.04 kilometers with an albedo of 0.068.[7]

The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.10 – a compromise value between the darker C-type and brighter S-type asteroids – and calculates a diameter of 19.21 kilometers based on an absolute magnitude of 11.7.[3][a]

Notes

  1. ^ a b c For central-belt asteroids with 2.6 < a < 2.7, the LCDB assumes an "S/C" class with an albedo of 0.10, a compromise between the stony (p=0.20) and carbonaceous (p=0.057) asteroids, see LCDB readme

References

  1. ^ a b c d "JPL Small-Body Database Browser: 1555 Dejan (1941 SA)" (2017-03-21 last obs.). Jet Propulsion Laboratory. Retrieved 20 September 2017.
  2. ^ a b Schmadel, Lutz D. (2007). "(1555) Dejan". Dictionary of Minor Planet Names – (1555) Dejan. Springer Berlin Heidelberg. p. 123. doi:10.1007/978-3-540-29925-7_1556. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f "LCDB Data for (1555) Dejan". Asteroid Lightcurve Database (LCDB). Retrieved 20 September 2017.
  4. ^ 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.
  5. ^ 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. S2CID 118745497. Retrieved 20 September 2017.
  6. ^ 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". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. S2CID 35447010.
  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. (online, AcuA catalog p. 153)
  8. ^ a b Brines, Pedro; Lozano, Juan; Rodrigo, Onofre; Fornas, A.; Herrero, David; Mas, Vicente; et al. (April 2017). "Sixteen Asteroids Lightcurves at Asteroids Observers (OBAS) - MPPD: 2016 June-November". The Minor Planet Bulletin. 44 (2): 145–149. Bibcode:2017MPBu...44..145B. ISSN 1052-8091. Retrieved 20 September 2017.
  9. ^ a b "1555 Dejan (1941 SA)". Minor Planet Center. Retrieved 20 September 2017.