(12538) 1998 OH

Orbit and classification

is a member of the Apollo group of asteroids, which are Earth-crossing asteroids. They are the largest group of near-Earth objects with approximately 10,000 known members.

It orbits the Sun at a distance of 0.9–2.2 AU in 1 year and 11 months (699 days). Its orbit has an eccentricity of 0.41 and an inclination of 25° with respect to the ecliptic. The body's observation arc begins with a precovery taken at Palomar Observatory in October 1991, more than 7 years prior to its official discovery observation at Haleakala.

The asteroid has an Earth minimum orbital intersection distance of 0.0280 AU, which corresponds to 10.9 lunar distances and makes it a potentially hazardous asteroid due to its sufficiently large size. It will pass close to Earth in 2042 and 2132, at distances of 0.0292 AU and 0.0317 AU, respectively.

Physical characteristics

In the SMASS classification, is a common stony S-type asteroid.

In 2014, several rotational lightcurves of were obtained from photometric observations by American astronomer Brian Warner at the Palmer Divide Station in California, by the Spanish amateur astronomer group OBAS, and by astronomers of the EURONEAR lightcurve NEO survey. Lightcurve analysis gave a rotation period of 5.154 hours with an alternative period solution of 2.58 hours, or half the period. The asteroid's brightness amplitude is rather low with a maximum between 0.11 and 0.20 magnitude, which is indicative for a spherical rather than elongated shape ().

According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, measures 1.663 kilometers in diameter and its surface has an albedo of 0.232. The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 2.06 kilometers based on an absolute magnitude of 15.8.

Notes

References

References

1. "JPL Small-Body Database Browser: 12538 (1998 OH)". Jet Propulsion Laboratory.
2. "12538 (1998 OH)". Minor Planet Center.
3. "MPC/MPO/MPS Archive". Minor Planet Center.
4. (December 2011). "NEOWISE Observations of Near-Earth Objects: Preliminary Results". The Astrophysical Journal.
5. "LCDB Data for (12538)". Asteroid Lightcurve Database (LCDB).
6. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal.
7. Warner, Brian D.. (April 2015). "Near-Earth Asteroid Lightcurve Analysis at CS3-Palmer Divide Station: 2014 October-December". The Minor Planet Bulletin.
8. (April 2017). "Seven Near-Earth Asteroids at Asteroids Observers (OBAS) - MPPD: 2016 June-November". The Minor Planet Bulletin.
9. (August 2017). "The EURONEAR Lightcurve Survey of Near Earth Asteroids". Earth.
10. Warner, Brian D.. (April 2017). "Near-Earth Asteroid Lightcurve Analysis at CS3-Palmer Divide Station: 2016 October-December". The Minor Planet Bulletin.