1704 Wachmann, provisional designation A924 EE, is a stony asteroid from the inner regions of the asteroid belt, approximately 7 kilometers in diameter. It was discovered by German astronomer Karl Reinmuth at Heidelberg Observatory on 7 March 1924. It was later named after astronomer Arno Wachmann.[2][8]

1704 Wachmann
1704Wachmann (Lightcurve Inversion).png
Light curve based 3D-model of Wachmann
Discovery [1]
Discovered byK. Reinmuth
Discovery siteHeidelberg Obs.
Discovery date7 March 1924
MPC designation(1704) Wachmann
Named after
Arno Wachmann
(German astronomer)[2]
A924 EE · 1947 CE
1957 BJ
main-belt · (inner)[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc93.16 yr (34,026 days)
Aphelion2.4163 AU
Perihelion2.0292 AU
2.2228 AU
3.31 yr (1,210 days)
0° 17m 50.64s / day
Physical characteristics
6.934±0.070 km[5]
7.82 km (calculated)[3]
3.314±0.001 h[6]
0.20 (assumed)[3]
12.9[1][3] · 12.97±0.13[7] · 13.3[5]


Classification and orbitEdit

The S-type asteroid orbits the Sun in the inner main-belt at a distance of 2.0–2.4 AU once every 3 years and 4 months (1,210 days). Its orbit has an eccentricity of 0.09 and an inclination of 1° with respect to the ecliptic.[1] No precoveries were taken. The asteroid's observation arc begins 3 days after its official discovery observation.[8]

Physical characteristicsEdit


In April 2007, a rotational lightcurve Wachmann was obtained at the U.S. Sandia View Observatory in New Mexico (H03). Lightcurve analysis gave a well-defined rotation period of 3.314±0.001 hours with a brightness variation of 0.40 magnitude (U=3).[6]

Diameter and albedoEdit

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Wachmann measures 6.6 and 6.9 kilometers in diameter, and its surface has an albedo of 0.177 and 0.193, respectively,[4][5] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 7.8 kilometers, based on an absolute magnitude of 12.9.[3]


This minor planet was named for Arno Wachmann (1902–1990), long-time astronomer at the Bergedorf Observatory in Hamburg, discoverer of minor planets and comets, and observer of variable and binary stars. He is best known for the co-discovery of the three "Schwassmann–Wachmann" comets, 29P, 31P and 73P.[2] The official naming citation was published by the Minor Planet Center before November 1977 (M.P.C. 3933).[9]


  1. ^ a b c d "JPL Small-Body Database Browser: 1704 Wachmann (A924 EE)" (2017-05-05 last obs.). Jet Propulsion Laboratory. Retrieved 7 June 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). "(1704) Wachmann". Dictionary of Minor Planet Names – (1704) Wachmann. Springer Berlin Heidelberg. pp. 135–136. doi:10.1007/978-3-540-29925-7_1705. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f "LCDB Data for (1704) Wachmann". Asteroid Lightcurve Database (LCDB). Retrieved 20 July 2016.
  4. ^ 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 8 December 2016.
  5. ^ 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.
  6. ^ a b Julian, II, William M. (March 2008). "Period Determination for 1704 Wachmann". The Minor Planet Bulletin. 35 (1): 4. Bibcode:2008MPBu...35....4J. ISSN 1052-8091. Retrieved 20 July 2016.
  7. ^ 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 20 July 2016.
  8. ^ a b "1704 Wachmann (A924 EE)". Minor Planet Center. Retrieved 20 July 2016.
  9. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 20 July 2016.

External linksEdit