2123 Vltava, provisional designation 1973 SL2, is a stony Koronian asteroid from the outer region of the asteroid belt, approximately 15 kilometers in diameter. It was discovered on 22 September 1973, by Soviet–Russian astronomer Nikolai Chernykh at the Crimean Astrophysical Observatory on the Crimean peninsula in Nauchnyj.[10] It is named for the river Vltava (Moldau).[2]
Classification and orbit
The S-type asteroid is a member of the Koronis family, which is named after 158 Koronis and consists of about 300 known bodies with nearly co-planar ecliptical orbits. The asteroid orbits the Sun in the outer main-belt at a distance of 2.6–3.1 AU once every 4 years and 10 months (1,767 days). Its orbit has an eccentricity of 0.08 and an inclination of 1° with respect to the ecliptic.[1] A first precovery taken at Heidelberg in 1934, extends the body's observation arc by 39 years prior to its official discovery observation at Nauchnyj.[10]
Physical characteristics
Rotation period
Between 1998 and 2005, a survey of members of the Koronis family by seven different observatories obtained a large number of rotational lightcurves from . For Vltava, the survey gave an ambiguous rotation period of 34.0 hours with a brightness variation of 0.21 in magnitude (U=2).[8] In 2014, photometric observations at the Palomar Transient Factory in California rendered a lightcurve with an alternative solution of 16.2954 hours, or about half the period previously found, with an amplitude of 0.19 magnitude (U=2).[7]
This minor planet was named for the Vltava(Moldau), the longest river within the Czech Republic, running through the city of Prague.[2] The approved naming citation was published by the Minor Planet Center on 1 April 1980 (M.P.C. 5283).[11]