917 Lyka

917 Lyka
Discovery[1]
Discovered byG. Neujmin
Discovery siteSimeiz Obs.
Discovery date5 September 1915
Designations
(917) Lyka
Named after
Lyka, a friend of the discoverer's sister[2]
A915 RR · 1950 BS
1951 JJ · 1915 S4
1915 Σ4
main-belt[1][3] · (inner)
background[4][5]
Orbital characteristics[3]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 0
Observation arc100.18 yr (36,591 d)
Aphelion2.8590 AU
Perihelion1.9035 AU
2.3812 AU
Eccentricity0.2006
3.67 yr (1,342 d)
181.91°
0° 16m 5.52s / day
Inclination5.1264°
343.38°
359.90°
Physical characteristics
  • 28.10±3.9 km[6]
  • 31.29±0.49 km[7]
  • 34.878±0.184 km[8]
7.867±0.006 h
  • 0.056±0.008[8]
  • 0.072±0.003[7]
  • 0.0891±0.031[6]
X (S3OS2)[9]
11.6[1][3]

917 Lyka (prov. designation: A915 RR or 1915 S4) is a background asteroid, approximately 32 kilometers (20 miles) in diameter, located in the inner region of the asteroid belt. It was discovered on 5 September 1915, by Russian astronomer Grigory Neujmin at the Simeiz Observatory on the Crimean peninsula.[1] The X-type asteroid has a rotation period of 7.9 hours and is likely spherical in shape. It was named after Lyka, a friend of the discoverer's sister.[2]

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  8. ^ a b Cite error: The named reference Masiero-2014 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Lazzaro-2004 was invoked but never defined (see the help page).