8026 Johnmckay

8026 Johnmckay
Discovery [1]
Discovered by E. F. Helin
Discovery site Palomar Obs.
Discovery date 8 May 1991
Designations
MPC designation 8026 Johnmckay
Named after
 John B. McKay (test pilot)[2]
1991 JA1 · 1989 UF2
main-belt · Hungaria [3]
Orbital characteristics [1]
Epoch 16 February 2017 (JD 2457800.5)
Uncertainty parameter 0
Observation arc 25.81 yr (9,427 days)
Aphelion 2.0697 AU
Perihelion 1.7803 AU
1.9250 AU
Eccentricity 0.0752
2.67 yr (976 days)
107.70°
0° 22m 8.4s / day
Inclination 19.935°
217.71°
145.62°
Known satellites 1 [4]
Earth MOID 0.8003 AU
Physical characteristics
Dimensions 1.690±0.239 km[5][6]
2.54 km (calculated)[3]
355±5 h[7]
372±5 h[8]
0.30 (assumed)[3]
0.815±0.196[5][6]
E [3]
14.60±0.44[9] · 14.7[5] · 14.9[1][3]

    8026 Johnmckay, provisional designation 1991 JA1, is a binary[4] Hungaria asteroid and very slow rotator from the inner regions of the asteroid belt, approximately 2 kilometers in diameter. It was discovered on 8 May 1991, by American female astronomer Eleanor Helin at the U.S. Palomar Observatory, California.[2]

    The bright E-type asteroid is a member of the Hungaria family, which form the innermost dense concentration of asteroids in the Solar System. It orbits the Sun at a distance of 1.8–2.1 AU once every 2 years and 8 months (976 days). Its orbit has an eccentricity of 0.08 and an inclination of 20° with respect to the ecliptic.[1] The fist observation was made at the discovering observatory in 1989, extending the asteroid's observation arc by almost 2 years prior to its discovery.[2]

    According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the asteroid measures 1.7 kilometers in diameter and its surface has an exceptionally high albedo of 0.81, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for Hungaria asteroids of 0.30, and calculates a diameter of 2.5 kilometers, based on an absolute magnitude of 14.9.[3][5][6]

    Two rotational light-curves were obtained for this asteroid from photometric observations by U.S. astronomer Brian D. Warner at the Palmer Divide Station (PDO), Colorado. In August 2010, the first light-curve gave a long rotation period of 372±5 hours with a brightness variation of 1.0 in magnitude (U=3).[8] The second light-curve from June 2015, gave a similar period of 355±5 with an amplitude of 0.66 in magnitude (U=2).[7]

    In 2010 a small asteroid moon was discovered around this asteroid. It has an orbital period of 2.300±0.001 hours,[4] while observations at the PDO gave it a period of 2.2981 and 14.93 hours, respectively.[3][8][7]

    The minor planet was named in memory of NASA test pilot John B. McKay (1922–1975), one of the first pilots assigned to fly the North American X-15. He was also assigned to the X-1E and to the D-558-II. He died in 1975, from injuries he had sustained during a X-15 crash. In 2005, he received posthumous the astronaut badge for a reached peak-altitude of 89,900 metres (295,000 feet).[2] Naming citation was published on 7 February 2012 (M.P.C. 78269).[10]

    References

    1. 1 2 3 4 "JPL Small-Body Database Browser: 8026 Johnmckay (1991 JA1)" (2015-08-19 last obs.). Jet Propulsion Laboratory. Retrieved 4 December 2016.
    2. 1 2 3 4 "8026 Johnmckay (1991 JA1)". Minor Planet Center. Retrieved 11 August 2016.
    3. 1 2 3 4 5 6 7 "LCDB Data for (8026) Johnmckay". Asteroid Lightcurve Database (LCDB). Retrieved 11 August 2016.
    4. 1 2 3 Johnston, Robert. "(8026) Johnmckay". johnstonsarchive.net. Retrieved 29 May 2015.
    5. 1 2 3 4 Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results" (PDF). The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407Freely accessible. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 11 August 2016.
    6. 1 2 3 Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096Freely accessible. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 4 December 2016.
    7. 1 2 3 Warner, Brian D. (October 2015). "Asteroid Lightcurve Analysis at CS3-Palmer Divide Station: 2015 March-June". The Minor Planet Bulletin. 42 (4): 267–276. Bibcode:2015MPBu...42..267W. ISSN 1052-8091. Retrieved 11 August 2016.
    8. 1 2 3 Warner, Brian D. (January 2011). "A Quartet of Known and Suspected Hungaria Binary Asteroids". The Minor Planet Bulletin. 38 (1): 33–36. Bibcode:2011MPBu...38...33W. ISSN 1052-8091. Retrieved 11 August 2016.
    9. ↑ Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762Freely accessible. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. Retrieved 11 August 2016.
    10. ↑ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 11 August 2016.

    External links

    This article is issued from Wikipedia - version of the 12/4/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.