Jump to content

1669 Dagmar

From Wikipedia, the free encyclopedia
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

1669 Dagmar
Discovery[1]
Discovered byK. Reinmuth
Discovery siteHeidelberg Obs.
Discovery date7 September 1934
Designations
(1669) Dagmar
Named after
Generic name
(common German name)[2]
1934 RS · 1943 GE
1950 PX · 1953 AD
1957 WA · 1959 CV
1962 RH
main-belt · Themis[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc82.66 yr (30,190 days)
Aphelion3.4870 AU
Perihelion2.7920 AU
3.1395 AU
Eccentricity0.1107
5.56 yr (2,032 days)
126.58°
0° 10m 37.92s / day
Inclination0.9409°
18.979°
178.21°
Physical characteristics
Dimensions35.78±2.4 km (IRAS:17)[4]
42.377±0.188 km[5]
42.99±2.86 km[6]
43.00±0.77 km[7]
45.194±0.620 km[8]
Mass(3.98±0.80)×1016 kg[6]
Mean density
0.95±0.27 g/cm3[6]
12 h[9]
0.0354±0.0061[8]
0.039±0.007[5][7]
0.0565±0.008 (IRAS:17)[4]
Tholen = G:[1] · G:[3]
B–V = 0.730[1]
U–B = 0.460[1]
10.91±0.18[10] · 10.97 (IRAS:17)[1][3][4] · 10.97[7][8]

1669 Dagmar, provisional designation 1934 RS, is a rare-type Themistian asteroid from the outer region of the asteroid belt, approximately 42 kilometers in diameter. It was discovered on 7 September 1934, by German astronomer Karl Reinmuth at Heidelberg Observatory in southern Germany, and named after a common German feminine name.[2][11]

Classification and orbit

The asteroid is a member of the Themis family, a large group of asteroids in the outer main-belt. It orbits the Sun at a distance of 2.8–3.5 AU once every 5 years and 7 months (2,032 days). Its orbit has an eccentricity of 0.11 and an inclination of 1° with respect to the ecliptic.[1] As no precoveries were taken, and no prior identifications were made, Dagmar's observation arc begins with its official discovery observation.[11]

Physical characteristics

Dagmar has a rare spectra of a G-type asteroid (or Cg-type in the SMASS taxonomy), similar to 1 Ceres, the largest asteroid and only dwarf planet in the asteroid belt.[1]

Rotation period

Astronomer Federico Manzini obtained a provisional lightcurve of Dagmar from photometric observations in March 2004. It gave a tentative rotation period of 12 hours with a brightness variation of 0.15 magnitude (U=1).[9] As of 2017, no secure period has yet been published.[1]

Diameter and albedo

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, Dagmar measures between 35.78 and 45.194 kilometers in diameter, and its surface has an albedo between 0.035 and 0.057.[4][5][7][8] The Collaborative Asteroid Lightcurve Link adopts the results obtained by 17 observations made by IRAS, that is an albedo of 0.0565 and a diameter of 35.78 kilometers with an absolute magnitude of 10.97.[3]

Naming

This minor planet was named by the discoverer after a common German feminine name. No special meaning is assigned to this name.[2] The official naming citation was published by the Minor Planet Center on 15 December 1968 (M.P.C. 2901).[12]

References

  1. ^ a b c d e f g h i "JPL Small-Body Database Browser: 1669 Dagmar (1934 RS)" (2017-05-04 last obs.). Jet Propulsion Laboratory. Retrieved 6 June 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). "(1669) Dagmar". Dictionary of Minor Planet Names – (1669) Dagmar. Springer Berlin Heidelberg. p. 133. doi:10.1007/978-3-540-29925-7_1670. ISBN 978-3-540-00238-3.
  3. ^ a b c d "LCDB Data for (1669) Dagmar". Asteroid Lightcurve Database (LCDB). Retrieved 23 December 2016.
  4. ^ 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 – IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 17 October 2019.
  5. ^ 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 23 December 2016.
  6. ^ a b c Carry, B. (December 2012). "Density of asteroids". Planetary and Space Science. 73 (1): 98–118. arXiv:1203.4336. Bibcode:2012P&SS...73...98C. doi:10.1016/j.pss.2012.03.009. Retrieved 23 December 2016.
  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 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.
  9. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1669) Dagmar". Geneva Observatory. Retrieved 23 December 2016.
  10. ^ 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 23 December 2016.
  11. ^ a b "1669 Dagmar (1934 RS)". Minor Planet Center. Retrieved 23 December 2016.
  12. ^ Schmadel, Lutz D. "Appendix – Publication Dates of the MPCs". Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008). Springer Berlin Heidelberg. p. 221. doi:10.1007/978-3-642-01965-4. ISBN 978-3-642-01964-7.