1669 Dagmar

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1669 Dagmar
Discovery [1]
Discovered by K. Reinmuth
Discovery site Heidelberg 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 arc 82.66 yr (30,190 days)
Aphelion 3.4870 AU
Perihelion 2.7920 AU
3.1395 AU
Eccentricity 0.1107
5.56 yr (2,032 days)
126.58°
0° 10m 37.92s / day
Inclination 0.9409°
18.979°
178.21°
Physical characteristics
Dimensions 35.78±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]

    Contents

    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. 1 2 3 4 5 6 7 8 9 "JPL Small-Body Database Browser: 1669 Dagmar (1934 RS)" (2017-05-04 last obs.). Jet Propulsion Laboratory . Retrieved 6 June 2017.
    2. 1 2 3 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. 1 2 3 4 "LCDB Data for (1669) Dagmar". Asteroid Lightcurve Database (LCDB). Retrieved 23 December 2016.
    4. 1 2 3 4 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. 1 2 3 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. 1 2 3 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. 1 2 3 4 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. 1 2 3 4 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. 1 2 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. 1 2 "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.