13025 Zürich

13025 Zürich, provisional designation 1989 BA, is a stony Phocaea asteroid from the inner regions of the asteroid belt, approximately 5 kilometers in diameter. It was discovered on 28 January 1989, by Swiss astronomer Paul Wild at Zimmerwald Observatory near Bern, Switzerland, and later named for the Swiss city of Zürich.[2][7]

13025 Zürich
Discovery [1]
Discovered byP. Wild
Discovery siteZimmerwald Obs.
Discovery date28 January 1989
(13025) Zürich
Named after
Zürich (Swiss city)[2]
1989 BA
main-belt · Phocaea[3][4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc41.25 yr (15,066 days)
Aphelion3.0429 AU
Perihelion1.7221 AU
2.3825 AU
3.68 yr (1,343 days)
0° 16m 4.8s / day
Physical characteristics
Dimensions4.89±0.10 km[5]
5.28 km (calculated)[3]
18.53±0.02 h[6]
0.23 (assumed)[3]
13.40[5] · 13.6[1][3]

Orbit and classificationEdit

The stony S-type asteroid is a member of the Phocaea family (701),[4] a rather small group of asteroids with similar orbital characteristics, named after its largest member, 25 Phocaea. It orbits the Sun in the inner main-belt at a distance of 1.7–3.0 AU once every 3 years and 8 months (1,343 days). Its orbit has an eccentricity of 0.28 and an inclination of 24° with respect to the ecliptic.[1] A first precovery was obtained at the Australian Siding Spring Observatory in 1975, extending the asteroid's observation arc by 14 years prior to its discovery.[7]


In November 2006, American astronomer Brian Warner obtained a rotational lightcurve from photometric observations taken at his Palmer Divide Observatory in Colorado. The lightcurve showed a rotation period of 18.53±0.02 hours and a brightness variation of 0.24 in magnitude (U=2+).[6]

Diameter and albedo estimatesEdit

According to the survey carried out by NASA's space-based Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the asteroid measures 4.9 kilometers in diameter and its surface has a high albedo of 0.32,[5] while the Collaborative Asteroid Lightcurve Link assumes an albedo of 0.23 and hence calculates a somewhat larger diameter of 5.3 kilometers with an absolute magnitude of 13.6.[3]


The minor planet is named after Zürich, Switzerland's largest city and economic center, located at the northwestern tip of Lake Zürich. It was founded by the Romans in the 1st century BC on the rivers Sihl and Limmat and was then called Turicum.[2] The official naming citation was published by the Minor Planet Center on 1 November 2001 (M.P.C. 43762).[8]


  1. ^ a b c d "JPL Small-Body Database Browser: 13025 Zurich (1989 BA)" (2016-09-07 last obs.). Jet Propulsion Laboratory. Retrieved 24 June 2017.
  2. ^ a b c Schmadel, Lutz D. (2007). "(13025) Zürich". Dictionary of Minor Planet Names – (13025) Zürich. Springer Berlin Heidelberg. p. 792. doi:10.1007/978-3-540-29925-7_8727. ISBN 978-3-540-00238-3.
  3. ^ a b c d e f "LCDB Data for (13025) Zurich". Asteroid Lightcurve Database (LCDB). Retrieved 17 May 2016.
  4. ^ a b "Asteroid 13025 Zurich – Nesvorny HCM Asteroid Families V3.0". Small Bodies Data Ferret. Retrieved 27 October 2019.
  5. ^ 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 17 May 2016.
  6. ^ a b Warner, Brian D. (June 2007). "Asteroid Lightcurve Analysis at the Palmer Divide Observatory - September-December 2006". The Minor Planet Bulletin. 34 (2): 32–37. Bibcode:2007MPBu...34...32W. ISSN 1052-8091. Retrieved 6 April 2016.
  7. ^ a b "13025 Zurich (1989 BA)". Minor Planet Center. Retrieved 6 April 2016.
  8. ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 17 May 2016.

External linksEdit