(1677) Tycho Brahe

1677 Tycho Brahe
001677-asteroid shape model (1677) Tycho Brahe.png
Tycho Brahe modeled from its lightcurve
Discovered byY. Väisälä
Discovery siteTurku Obs.
Discovery date6 September 1940
(1677) Tycho Brahe
Named after
Tycho Brahe[2]
(Danish astronomer)
1940 RO · 1928 SP
1935 FL · 1952 QN1
1952 SD1 · A916 UA
main-belt[1][3] · (middle)
Maria[4] · Eunomia[5]
Orbital characteristics[3]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc82.92 yr (30,285 d)
Aphelion2.8037 AU
Perihelion2.2607 AU
2.5322 AU
4.03 yr (1,472 d)
0° 14m 40.56s / day
Physical characteristics
Mean diameter
8.90±0.72 km[6]
11.686±0.116 km[7]
11.784±0.093 km[8]
13.26 km (calculated)[5]
3.89±0.06 h[9]
0.21 (assumed)[5]

1677 Tycho Brahe, provisional designation 1940 RO, is a stony Marian asteroid from the central region of the asteroid belt, approximately 12 kilometers (7.5 miles) in diameter. It was discovered on 6 September 1940, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland.[1] The common stony S-type asteroid has a short rotation period of 3.89 hours.[5] It was later named after Tycho Brahe, one of the fathers of astronomy.[2]

Classification and orbit[]

When applying the hierarchical clustering method to its proper orbital elements, Tycho Brahe is a member of the Maria family (506),[4] a large family of stony asteroids.[11]: 23  Based on osculating Keplerian orbital elements, the asteroid has also been classified as a member of the Eunomia family (502), the largest family in the intermediate main belt with more than 5,000 members.[5]

It orbits the Sun in the central main-belt at a distance of 2.3–2.8 AU once every 4.03 years (1,472 days; semi-major axis of 2.53 AU). Its orbit has an eccentricity of 0.11 and an inclination of 15° with respect to the ecliptic.[3] The asteroid was first observed as A916 UA at Bergedorf Observatory in October 1916, extending the body's observation arc by 24 years prior to its official discovery observation at Turku.[1]

Physical characteristics[]

The asteroid has been characterized as a stony S-type by Pan-STARRS survey, and in the SDSS-MFB (Masi Foglia Binzel) taxonomy,[5][10][a] which agree with the overall spectral type for members of the Maria family.[11]: 23 

Rotation period[]

In July 2012, a rotational lightcurve of Tycho Brahe was obtained by Renata Violante and Martha Leake, that gave a short rotation period of 3.89 hours with a brightness variation of 0.38 magnitude (U=2+).[5][9]

Diameter and albedo[]

According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Tycho Brahe measures 11.78 kilometers in diameter, and its surface has an albedo of 0.221 (revised 2014-figures).[8] The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.21, derived from the family's largest member and namesake, 15 Eunomia, and calculates a diameter of 13.26 kilometers, based on an absolute magnitude of 11.7.[5]


This minor planet is named for the great Danish-born astronomer Tycho Brahe (1546–1601) an early forerunner and father of modern astronomy. He is known for his unprecedented precise measurements in the pre-telescopic era.[2] The official naming citation was published by the Minor Planet Center on 15 October 1977 (M.P.C. 4236).[12] Brahe is also honored by the prominent crater Tycho in the southern highlands of the Moon and by the Martian crater Tycho Brahe.[2] The bright supernova, SN 1572, is also known as Tycho's Nova.


  1. ^ a b Search for Unusual Spectroscopic Candidates Among 40313 minor planets from the 3rd Release of the Sloan Digital Sky Survey Moving Object Catalog (publication). SDSS-MFB (Masi Foglia Binzel) taxonomy (catalog).


  1. ^ a b c d "1677 Tycho Brahe (1940 RO)". Minor Planet Center. Retrieved 25 April 2018.
  2. ^ a b c d Schmadel, Lutz D. (2007). "(1677) Tycho Brahe". Dictionary of Minor Planet Names – (1677) Tycho Brahe. Springer Berlin Heidelberg. p. 133. doi:10.1007/978-3-540-29925-7_1678. ISBN 978-3-540-00238-3.
  3. ^ a b c d "JPL Small-Body Database Browser: 1677 Tycho Brahe (1940 RO)" (2018-02-26 last obs.). Jet Propulsion Laboratory. Retrieved 25 April 2018.
  4. ^ a b "Asteroid 1677 Tycho Brahe – Nesvorny HCM Asteroid Families V3.0". Small Bodies Data Ferret. Retrieved 26 October 2019.
  5. ^ a b c d e f g h i j "LCDB Data for (1677) Tycho Brahe". Asteroid Lightcurve Database (LCDB). Retrieved 23 December 2016.
  6. ^ a b c Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Nugent, C.; et al. (November 2012). "Preliminary Analysis of WISE/NEOWISE 3-Band Cryogenic and Post-cryogenic Observations of Main Belt Asteroids". The Astrophysical Journal Letters. 759 (1): 5. arXiv:1209.5794. Bibcode:2012ApJ...759L...8M. doi:10.1088/2041-8205/759/1/L8.
  7. ^ a b c 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.
  8. ^ 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.
  9. ^ a b Violante, R.; Leake, M. A. (December 2012). "Photometry and Lightcurve Analysis of 7 Main-Belt Asteroids". Journal of the Southeastern Association for Research in Astronomy. 7: 41–44. Bibcode:2012JSARA...7...41V. Retrieved 23 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.
  11. ^ a b Nesvorný, D.; Broz, M.; Carruba, V. (December 2014). Identification and Dynamical Properties of Asteroid Families. Asteroids IV. pp. 297–321. arXiv:1502.01628. Bibcode:2015aste.book..297N. doi:10.2458/azu_uapress_9780816532131-ch016. ISBN 9780816532131.
  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 links[]