(6491) 1991 OA

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(6491) 1991 OA
Discovery [1]
Discovered by H. E. Holt
Discovery site Palomar Obs.
Discovery date 16 July 1991
Designations
MPC designation (6491) 1991 OA
NEO · Amor · PHA[1]
Orbital characteristics[1]
Epoch 16 February 2017 (JD 2457800.5)
Uncertainty parameter 0
Observation arc 24.35 yr (8,895 days)
Aphelion 3.9772 AU
Perihelion 1.0233 AU
2.5003 AU
Eccentricity 0.5907
3.95 yr (1,444 days)
165.17°
0° 14m 57.48s / day
Inclination 5.9449°
301.91°
323.58°
Earth MOID 0.0426 AU
Physical characteristics
Dimensions 0.52 km (derived)[2]
2.69 h[3]
0.20 (assumed)[2]
S[2]
18.77[2][3] · 18.9[1]

(6491) 1991 OA is a highly eccentric, stony asteroid, classified as near-Earth object and potentially hazardous asteroid, approximately half a kilometer in diameter. It was discovered on 16 July 1991, by American astronomer Henry E. Holt at the U.S. Palomar Observatory in California.[4]

The S-type body is an Amor asteroid – a subgroup of near-Earth asteroids that approach the orbit of Earth from beyond, but do not cross it. It orbits the Sun at a distance of 1.0–4.0 AU once every 3 years and 11 months (1,444 days). Its orbit has an eccentricity of 0.59 and an inclination of 6° with respect to the ecliptic.[1] Its minimum orbit intersection distance (MOID) with Earth is 0.0429 AU, and on 1 August 2086, it will make a close approach and pass by Earth at a distance of 0.09 AU (13,000,000 km).[5] The first precovery was taken at the Australian Siding Spring Observatory in March 1991, extending the asteroid's observation arc by 4 months prior to its discovery.[4]

In 2000, a rotational light-curve was published from photometric observations obtained by the Near-Earth Objects Follow-up Program during the early 1990s. The light-curve rendered a rotation period of 2.69 hours with an brightness amplitude of 0.08 in magnitude (U=2).[3] The Collaborative Asteroid Lightcurve Link (CALL) assumes an albedo of 0.20 and derives a diameter of 0.53 kilometers, based on an absolute magnitude of 18.77.[2]

References[edit]

  1. ^ a b c d e "JPL Small-Body Database Browser: 6491 (1991 OA)" (2015-07-25 last obs.). Jet Propulsion Laboratory. Retrieved 14 December 2016. 
  2. ^ a b c d e "LCDB Data for (6491)". Asteroid Lightcurve Database (LCDB). Retrieved 24 July 2016. 
  3. ^ a b c Erikson, A.; Mottola, S.; Lagerros, J. S. V.; Lindgren, M.; Piironen, J.; Oja, T.; et al. (October 2000). "The Near-Earth Objects Follow-up Program. III. 32 Lightcurves for 12 Objects from 1992 and 1995". Icarus. 147 (2): 487–497. Bibcode:2000Icar..147..487E. doi:10.1006/icar.2000.6457. Retrieved 1 January 2016. 
  4. ^ a b "6491 (1991 OA)". Minor Planet Center. Retrieved 24 July 2016. 
  5. ^ "JPL Close-Approach Data: 6491 (1991 OA)". Retrieved 24 March 2012. 2011-09-29 last obs 

External links[edit]