2308 Schilt, provisional designation 1967 JM, is a stony Eunomia asteroid from the asteroid belt, approximately 17 kilometers in diameter. It was discovered on 6 May 1967, by Argentine astronomer Carlos Cesco together with American astronomer Arnold Klemola at the Yale–Columbia Southern Station at Leoncito Astronomical Complex in Argentina.[8]

2308 Schilt
Discovery [1]
Discovered byC. U. Cesco
A. R. Klemola
Discovery siteEl Leoncito
(Yale–Columbia Southern Station)
Discovery date6 May 1967
MPC designation(2308) Schilt
Named after
Jan Schilt (astronomer)[2]
1967 JM · 1926 GP
1930 DR · 1972 TX7
1976 UH12 · 1980 VF
1981 YM
main-belt · Eunomia[3]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc82.71 yr (30,210 days)
Aphelion2.9873 AU
Perihelion2.1114 AU
2.5494 AU
4.07 yr (1,487 days)
0° 14m 31.56s / day
Physical characteristics
Dimensions13.79±0.57 km[4]
17.51 km (derived)[3]
17.54±0.8 km (IRAS:18)[1]
17.626±0.220 km[5]
17.719±0.098 km[6]
9.759±0.002 h[7]
9.767±0.005 h[a]
0.1001 (derived)[1]
0.1094±0.011 (IRAS:18)[1]
SMASS = S[1] · S[3]
11.8[4][5] · 11.9[1][3]

Orbit and classificationEdit

Schilt is a member of the Eunomia family, a large group of stony asteroids and the most prominent family in the intermediate main-belt. It orbits the Sun in the central main-belt at a distance of 2.1–3.0 AU once every 4 years and 1 month (1,487 days). Its orbit has an eccentricity of 0.17 and an inclination of 14° with respect to the ecliptic.[1] The asteroids observation arc begins with its discovery in 1967. However, the first (unused) precovery was already taken at Heidelberg Observatory in 1921.[8]

Physical characteristicsEdit

In the SMASS taxonomy, Schilt has been characterized as a common S-type asteroid.[1]

Rotation periodEdit

A rotational lightcurve was obtained based on photometric observations at the Australian Oakley Southern Sky Observatory in August 2012. The lightcurve showed a period of 9.759±0.002 hours with a brightness amplitude of 0.44 in magnitude (U=3).[7] A previous observation by Argentine astronomer Salvador Mazzone at the Observatorio Astronómico Salvador gave a similar period of 9.767±0.005 with an amplitude of 0.42 in magnitude (U=3-).[a]

Diameter and albedoEdit

According to the surveys carried out by the Infrared Astronomical Satellite (IRAS) and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the asteroid measures between 13.8 and 17.7 kilometers in diameter and its surface has an albedo in the range of 0.10–0.17.[1][4][5] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.10 and a diameter of 17.5 kilometers.[3]


This minor planet was named after Dutch–American astronomer Jan Schilt (1894–1982), one of the founders of the discovering Columbia–Yale Southern Station in the early 1960s, for which he collaborated with local astronomer and with Yale's Dirk Brouwer, after whom the minor planet 1746 Brouwer is named. At Columbia University, Schilt's research included the dynamics and structure of galaxies, and improvements on measuring the brightness of stars.[2][9] The official naming citation was published by the Minor Planet Center on 11 December 1981 (M.P.C. 6531).[10]


  1. ^ a b Mazzone (2012) web: rotation period 9.767±0.005 hours with a brightness amplitude of 0.42 mag and an LCDB quality code of U=3-. See at astrosurf. Summary figures for (2308) Schilt at Collaborative Asteroid Lightcurve Link (CALL)


  1. ^ a b c d e f g h i j "JPL Small-Body Database Browser: 2308 Schilt (1967 JM)" (2016-11-21 last obs.). Jet Propulsion Laboratory. Retrieved 12 June 2017.
  2. ^ a b Schmadel, Lutz D. (2007). "(2308) Schilt". Dictionary of Minor Planet Names – (2308) Schilt. Springer Berlin Heidelberg. p. 188. doi:10.1007/978-3-540-29925-7_2309. ISBN 978-3-540-00238-3.
  3. ^ a b c d e "LCDB Data for (2308) Schilt". Asteroid Lightcurve Database (LCDB). Retrieved 18 May 2016.
  4. ^ a b c d 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. Retrieved 18 May 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. Retrieved 18 May 2016.
  6. ^ a b 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 7 December 2016.
  7. ^ a b Simpson, Gary; Chong, Elena; Gerhardt, Michael; Gorsky, Sean; Klaasse, Matthew; Kodalen, Brian; et al. (July 2013). "Asteroid Lightcurve Analysis at the Oakley Southern Sky Observatory: 2012 August - October". The Minor Planet Bulletin. 40 (3): 146–151. Bibcode:2013MPBu...40..146S. ISSN 1052-8091. Retrieved 18 May 2016.
  8. ^ a b "2308 Schilt (1967 JM)". Minor Planet Center. Retrieved 19 April 2016.
  9. ^ Milone, Eugene F. (2014). Schilt, Jan. The Biographical Encyclopedia of Astronomers. Springer Publishing. pp. 1939–1940. doi:10.1007/978-1-4419-9917-7_9396. ISBN 978-0-387-31022-0.
  10. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 18 May 2016.

External linksEdit