Discovery [1] | |
---|---|
Discovered by |
E. F. Helin J. Alu |
Discovery site | Palomar Obs. |
Discovery date | 24 September 1992 |
Designations | |
(10115) 1992 SK | |
1992 SK · 1985 SD 1985 TO2 | |
Apollo · NEO · PHA [1] [2] | |
Orbital characteristics [1] | |
Epoch 4 September 2017 ( JD 2458000.5) | |
Uncertainty parameter 0 | |
Observation arc | 63.57 yr (23,219 days) |
Aphelion | 1.6539 AU |
Perihelion | 0.8429 AU |
1.2484 AU | |
Eccentricity | 0.3248 |
1.39 yr (509 days) | |
47.505 ° | |
0° 42m 23.76s / day | |
Inclination | 15.322° |
8.9232° | |
233.63° | |
Earth MOID | 0.0449 AU · 17.5 LD |
Physical characteristics | |
Mean diameter | 0.90±0.20 km
[3] 0.938±0.294 km [4] 1.000±0.085 km [5] 1.0±0.2 [6] 1.18 km (calculated) [7] |
7.31±0.02 h
[8] 7.31832 h [9] 7.319 h [7] 7.323±0.005 h [10] 7.328±0.002 h [a] 7.320232±0.000010 h [6] | |
0.20 (assumed)
[7] 0.2799±0.1397 [5] 0.318±0.214 [4] 0.34±0.25 [3] 0.38±0.24 [11] | |
SMASS = S [1] · S [7] · S/Sq [12] | |
17.0 [1] [4] [5] [7] · 17.4 [a] | |
(10115) 1992 SK, is a stony near-Earth object and potentially hazardous asteroid on an eccentric orbit. It belongs to the group of Apollo asteroids and measures approximately 1 kilometer (0.6 miles) in diameter. It was discovered by American astronomers Eleanor Helin and Jeff Alu at the Palomar Observatory in California on 24 September 1992. [2]
The asteroid orbits the Sun at a distance of 0.8–1.7 AU once every 17 months (509 days). Its orbit has an eccentricity of 0.32 and an inclination of 15 ° with respect to the ecliptic. Its Earth minimum orbit intersection distance is 0.0449 AU (6,720,000 km). This makes the body a potentially hazardous asteroid, because its MOID is less than 0.05 AU and its diameter is greater than 150 meters. [1] The first precovery was obtained at Palomar Observatory in 1953, extending the asteroid's observation arc by 39 years prior to its discovery. [2]
In the SMASS classification, 1992 SK is characterized as a common stony S-type asteroid. [1]
Several rotational lightcurves form photometric observations have been obtained for this body. In 1999, Czech astronomer Petr Pravec constructed a lightcurve, that rendered a rotation period of 7.328 hours and a brightness variation of 0.72 in magnitude ( U=n/a). [a]
In March 2006, observations by astronomer David Polishook from the ground-based Wise Observatory, Israel, gave a rotation period of 7.31 and amplitude of 0.70 mag ( U=2), [8] and in November 2011, American astronomer Brian Warner at the Palmer Divide Observatory, Colorado, obtained the first well-defined period of 7.323 hours with an amplitude of 0.50 mag ( U=3). [10]
The rotation period of 1992 SK is slowly accelerating due to the YORP effect. [6]
According to the surveys carried out by NASA's space-based Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the asteroid measures 1.0 and 0.94 kilometers in diameter and its surface has an albedo of 0.28 to 0.32, respectively. [4] [5] The ExploreNEOs project finds an albedo of 0.34, with an diameter of 0.9 kilometers, [3] and the Collaborative Asteroid Lightcurve Link calculates a diameter of 1.18 kilometers based on an assumed standard albedo for stony asteroids of 0.20 and an absolute magnitude of 17.0. [7]
This minor planet was numbered by the Minor Planet Center on 2 March 1999. [13] As of 2019 [update], it has not been named. [2]