1170 Siva

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1170 Siva
001170-asteroid shape model (1170) Siva.png
Modelled shape of Siva from its lightcurve
Discovered byE. Delporte
Discovery siteUccle Obs.
Discovery date29 September 1930
(1170) Siva
Named after
Shiva (Hindu deity)[2]
1930 SQ
Orbital characteristics[1]
Epoch 16 February 2017 (JD 2457800.5)
Uncertainty parameter 0
Observation arc85.19 yr (31,116 days)
Aphelion3.0245 AU
Perihelion1.6291 AU
2.3268 AU
3.55 yr (1,296 days)
0° 16m 39.72s / day
Earth MOID0.7263 AU
Mars MOID0.3760 AU
Physical characteristics
Dimensions7.68±2.18 km[6]
10.37±0.8 km (IRAS:2)[7]
12.13±0.89 km[8]
3.5 h[9]
4.98 h[a]
5.22±0.01 h[10]
0.1751±0.032 (IRAS:2)[7]
B–V = 0.864[1]
U–B = 0.452[1]
Tholen = S[1] · S[3][11]
12.00[11] · 12.18[6] · 12.43[1][3][7][8]

1170 Siva, provisional designation 1930 SQ, is a stony Phocaea asteroid and large Mars-crosser from the innermost regions of the asteroid belt, approximately 10 kilometers in diameter. It was discovered on 29 September 1930, by Belgian astronomer Eugène Delporte at Uccle Observatory in Belgium, and later named after the Hindu deity Shiva.[2][4]

Orbit and classification[edit]

Siva is a Mars-crossing asteroid, as it crosses the orbit of Mars at 1.666 AU. It is also a member of the Phocaea family (701).[5] It orbits the Sun at a distance of 1.6–3.0 AU once every 3 years and 7 months (1,296 days). Its orbit has an eccentricity of 0.30 and an inclination of 22° with respect to the ecliptic.[1] Siva was first observed at the Japanese Kwasan Observatory, 3 days prior to is discovery. The body's observation arc begins at Uccle, two weeks after its official discovery observation.[4]


This minor planet is named after Shiva, a Hindu deity often depicted with a third eye on his forehead and with a snake around his neck.[2] Naming citation was first mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 109).[2]

Physical characteristics[edit]

In the Tholen taxonomy, Siva is a stony S-type asteroid.[1]

Rotation period[edit]

Only fragmentary lightcurves of Siva have been obtained since 2001. They gave a rotation period between 3.5 and 5.22 hours with a small change in brightness of 0.04 to 0.1 magnitude (U=1/n.a./1).[9][10][a] As of 2017, no secure period has been published.[3]

Diameter and albedo[edit]

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, Siva measures between 7.68 and 12.13 kilometers in diameter, and its surface has an albedo between 0.128 and 0.40.[6][7][8] The Collaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.1751 and a diameter of 10.37 kilometers with an absolute magnitude of 12.43.[3] Siva belongs to the brightest known Mars-crossers.[12]


  1. ^ a b CALL (2011) web: rotation period 4.98 hours with a brightness amplitude of 0.1 mag. Summary figures at Collaborative Asteroid Lightcurve Link (CALL) for (1170) Siva


  1. ^ a b c d e f g h "JPL Small-Body Database Browser: 1170 Siva (1930 SQ)" (2016-01-21 last obs.). Jet Propulsion Laboratory. Retrieved 26 January 2017.
  2. ^ a b c d Schmadel, Lutz D. (2007). "(1170) Siva". Dictionary of Minor Planet Names – (1170) Siva. Springer Berlin Heidelberg. p. 98. doi:10.1007/978-3-540-29925-7_1171. ISBN 978-3-540-00238-3.
  3. ^ a b c d e "LCDB Data for (1170) Siva". Asteroid Lightcurve Database (LCDB). Retrieved 26 January 2017.
  4. ^ a b c "1170 Siva (1930 SQ)". Minor Planet Center. Retrieved 26 January 2017.
  5. ^ a b "Asteroid 1170 Siva – Nesvorny HCM Asteroid Families V3.0". Small Bodies Data Ferret. Retrieved 26 October 2019.
  6. ^ a b c d Nugent, C. R.; Mainzer, A.; Bauer, J.; Cutri, R. M.; Kramer, E. A.; Grav, T.; et al. (September 2016). "NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos". The Astronomical Journal. 152 (3): 12. arXiv:1606.08923. Bibcode:2016AJ....152...63N. doi:10.3847/0004-6256/152/3/63. Retrieved 26 January 2017.
  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. 12: IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 22 October 2019.
  8. ^ 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. (online, AcuA catalog p. 153)
  9. ^ a b Székely, P.; Kiss, L. L.; Szabó, Gy. M.; Sárneczky, K.; Csák, B.; Váradi, M.; et al. (August 2005). "CCD photometry of 23 minor planets". Planetary and Space Science. 53 (9): 925–936. arXiv:astro-ph/0504462. Bibcode:2005P&SS...53..925S. doi:10.1016/j.pss.2005.04.006. Retrieved 26 January 2017.
  10. ^ a b Behrend, Raoul. "Asteroids and comets rotation curves – (1170) Siva". Geneva Observatory. Retrieved 26 January 2017.
  11. ^ a b Carry, B.; Solano, E.; Eggl, S.; DeMeo, F. E. (April 2016). "Spectral properties of near-Earth and Mars-crossing asteroids using Sloan photometry". Icarus. 268: 340–354. arXiv:1601.02087. Bibcode:2016Icar..268..340C. doi:10.1016/j.icarus.2015.12.047. Retrieved 26 January 2017.
  12. ^ "JPL Small-Body Database Search Engine: orbital class (MCA) and H < 12.5 (mag)". JPL Solar System Dynamics.

External links[edit]