1841 Masaryk, provisional designation 1971 UO1, is a carbonaceous asteroid from the outer region of the asteroid belt, approximately 46 kilometers in diameter. It was discovered on 26 October 1971, by Czech astronomer Luboš Kohoutek at Bergedorf Observatory in Hamburg, Germany.[11] The asteroid was named after the first President of Czechoslovakia, Tomáš Garrigue Masaryk.[2]

1841 Masaryk
Discovery [1]
Discovered byL. Kohoutek
Discovery siteBergedorf Obs.
Discovery date26 October 1971
MPC designation(1841) Masaryk
Named after
Tomáš Garrigue Masaryk (Czechoslovak President)[2]
1971 UO1 · 1936 FW
1955 DE · 1959 VJ
1968 FG · 1970 QN
main-belt · (outer)[1]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc81.02 yr (29,591 days)
Aphelion3.7629 AU
Perihelion3.0796 AU
3.4213 AU
6.33 yr (2,311 days)
0° 9m 20.52s / day
Physical characteristics
Dimensions38.642±0.544 km[3]
43.77±0.83 km[5]
46.04 km (derived)[6]
46.07±2.5 km[7]
7.53±0.04 h[8]
7.54301±0.00001 h[9]
0.0364 (derived)[6]
P[3] · CX [10] · C[6]
10.8[3][5][7] · 10.9[1][6] · 10.94±0.19[10]

Orbit and classificationEdit

Masaryk orbits the Sun in the outer main-belt at a distance of 3.1–3.8 AU once every 6 years and 4 months (2,311 days). Its orbit has an eccentricity of 0.10 and an inclination of 3° with respect to the ecliptic.[1] First identified as 1936 FW at Uccle Observatory, Masaryk's first used observation was taken at Goethe Link Observatory in 1955, extending the body's observation arc by 16 years prior to its official discovery observation.[11]

Physical characteristicsEdit

The carbonaceous asteroid is characterized as a (darker) P-type and as a transitional CX-type by NEOWISE and PanSTARRS, respectively.[3][10]

Rotation periodEdit

In April 2006, a rotational lightcurve of Masaryk was obtained from photometric observations made by French amateur astronomer Pierre Antonini. It gave a rotation period of 7.53 hours with a brightness variation of 0.52 magnitude (U=2+).[8] The result agrees with a lightcurve published in March 2016, using sparse-in-time photometry data from the Lowell Photometric Database (U=n.a.).[9]

Diameter and albedoEdit

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, Masaryk measures between 38.6 and 46.1 kilometers in diameter, and its surface has an albedo between 0.039 and 0.057.[3][4][5][7] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.036 and a diameter of 46.0 kilometers with an absolute magnitude of 10.9.[6]


This minor planet was named in honor of the first president of the independent Czechoslovak Republic, Tomáš Garrigue Masaryk (1850–1937), statesman, philosopher and known for his humanistic ideas.[2] The official naming citation was published by the Minor Planet Center on 20 December 1974 (M.P.C. 3757).[12]


  1. ^ a b c d e "JPL Small-Body Database Browser: 1841 Masaryk (1971 UO1)" (2017-03-29 last obs.). Jet Propulsion Laboratory. Retrieved 8 June 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). "(1841) Masaryk". Dictionary of Minor Planet Names – (1841) Masaryk. Springer Berlin Heidelberg. p. 147. doi:10.1007/978-3-540-29925-7_1842. ISBN 978-3-540-00238-3.
  3. ^ 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.
  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 14 December 2016.
  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 17 October 2019. (online, AcuA catalog p. 153)
  6. ^ a b c d e "LCDB Data for (1841) Masaryk". Asteroid Lightcurve Database (LCDB). Retrieved 14 December 2016.
  7. ^ 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.
  8. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1841) Masaryk". Geneva Observatory. Retrieved 14 December 2016.
  9. ^ a b Durech, J.; Hanus, J.; Oszkiewicz, D.; Vanco, R. (March 2016). "Asteroid models from the Lowell photometric database". Astronomy and Astrophysics. 587: 6. arXiv:1601.02909. Bibcode:2016A&A...587A..48D. doi:10.1051/0004-6361/201527573. Retrieved 14 December 2016.
  10. ^ a b c 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 14 December 2016.
  11. ^ a b "1841 Masaryk (1971 UO1)". Minor Planet Center. Retrieved 14 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.

External linksEdit