[en] | (172034) 2001 WR1

(172034) 2001 WR1, provisional designation: 2001 WR1, is a sub-kilometer near-Earth object of the Amor group, approximately 650 meters (2,100 feet) in diameter. The S-type asteroid has been identified as a potential flyby target of the Hayabusa2 mission.[10] It was discovered on 17 November 2001, by astronomers with the Lincoln Near-Earth Asteroid Research at the Lincoln Laboratory’s Experimental Test Site near Socorro, New Mexico, in the United States.[1] The asteroid has a rotation period of 8.0 hours and possibly an elongated shape.[9] It remains unnamed since its numbering in December 2007.[1]

(172034) 2001 WR1
Discovery[1][2]
Discovered byLINEAR
Discovery siteLincoln Lab’s ETS
Discovery date17 November 2001
Designations
(172034) 2001 WR1
2001 WR1
NEO · Amor[1][3]
Orbital characteristics[3]
Epoch 1 July 2021 (JD 2459396.5)
Uncertainty parameter 0
Observation arc68.26 yr (24,933 d)
Aphelion1.5359 AU
Perihelion1.0185 AU
1.2772 AU
Eccentricity0.2025
1.44 yr (527 d)
200.68°
0° 40m 58.08s / day
Inclination25.030°
6.5141°
48.551°
Earth MOID0.0752 AU (29.3 LD)
Physical characteristics
8.0475±0.0003 h[7][a]
0.34[4][5][6]
S[8][9]
17.76[1][3]

Orbit and classification

2001 WR1 is an Amor asteroid – a subgroup of near-Earth asteroids that approach the orbit of Earth from beyond, but do not cross it. The object orbits the Sun at a distance of 1.02–1.54 AU once every 17 months (527 days; semi-major axis of 1.28 AU). Its orbit has an eccentricity of 0.20 and an inclination of 25° with respect to the ecliptic.[3] The body’s observation arc begins with its first observation in February 1953, more than 48 years prior to its official discovery observation at Socorro. The precovery was taken at Palomar Observatory and published by the Digitized Sky Survey.[1]

Close encounters

2001 WR1 has an Earth minimum orbital intersection distance of 0.0747 AU (11,200,000 km) which corresponds to 29.1 lunar distances.[3] In September 1926, it approached Earth to 0.1496 AU (22,400,000 km), its closest approach of all close encounters since 1900. Only in September 2199, it will approach Earth at a similar distance of 0.1514 AU (22,600,000 km).[3]

Hayabusa2 mission

2001 WR1 was proposed as a target of the Hayabusa2 extended mission for a flyby planned to occur on 27 June 2023.[10] When the spacecraft returned to Earth and delivered the sample capsule in December 2020, it was expected to retain 30 kg of xenon propellant, which can be used to extend its service and flyby new targets to explore.[10] However, this asteroid was not selected as a target for Hayabusa2; two other asteroids were selected instead.

Numbering and naming

This minor planet was numbered by the Minor Planet Center on 24 December 2007 (M.P.C. 61443).[11] As of 2021, it has not been named.[1]

Physical characteristics

2001 WR1 has been characterized as a common, stony S-type asteroid.[8]

Rotation period

In March 2018, a rotational lightcurve of 2001 WR1 was obtained from photometric observations by Brian Warner at the Palmer Divide Station (U82) in California. Lightcurve analysis gave a rotation period of 8.0475±0.0003 hours with a brightness amplitude of 0.95 magnitude (U=3), indicative of a non-spherical shape.[7][a]

Diameter and albedo

According to the survey carried out by the NEOWISE mission of NASA’s Wide-field Infrared Survey Explorer, 2001 WR1 has an albedo of 0.34 and measures 0.63 and 0.66 kilometers in diameter, respectively.[4][5][6] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for a stony asteroid of 0.20 and calculates a diameter of 0.818 kilometers based on an absolute magnitude of 17.8.[9]

Notes

  1. ^ a b Lightcurve plot of (172034) 2001 WR1 from Feb/Mar 2018 by Brian D. Warner at the Palmer Divide Observatory (U82). Rotation period 8.0475±0.0003 hours with a brightness amplitude of 0.95±0.03 mag. Quality code is 3. Summary figures at the CS3 and LCDB websites.

References

  1. ^ a b c d e f g “172034 (2001 WR1)”. Minor Planet Center. Retrieved 8 September 2021.
  2. ^ “Asteroid (172034) 2001 WR1”. Small Bodies Data Ferret. Retrieved 22 September 2018.
  3. ^ a b c d e f “JPL Small-Body Database Browser: 172034 (2001 WR1)” (2021-05-21 last obs.). Jet Propulsion Laboratory. Retrieved 8 September 2021.
  4. ^ a b c Mainzer, A. K.; Bauer, J. M.; Cutri, R. M.; Grav, T.; Kramer, E. A.; Masiero, J. R.; et al. (June 2016). “NEOWISE Diameters and Albedos V1.0”. NASA Planetary Data System: EAR-A-COMPIL-5-NEOWISEDIAM-V1.0. Bibcode:2016PDSS..247…..M. Retrieved 22 September 2018.
  5. ^ a b c Nugent, C. R.; Mainzer, A.; Masiero, J.; Bauer, J.; Cutri, R. M.; Grav, T.; et al. (December 2015). “NEOWISE Reactivation Mission Year One: Preliminary Asteroid Diameters and Albedos”. The Astrophysical Journal. 814 (2): 13. arXiv:1509.02522. Bibcode:2015ApJ…814..117N. doi:10.1088/0004-637X/814/2/117. S2CID 9341381.
  6. ^ a b c Nugent, C. R.; Mainzer, A.; Bauer, J.; Cutri, R. M.; Kramer, E. A.; Grav, T.; et al. (September 2016). “NEOWISE Reactivation Mission Year Two: Asteroid Diameters and Albedos”. The Astronomical Journal. 152 (3): 12. arXiv:1606.08923. Bibcode:2016AJ….152…63N. doi:10.3847/0004-6256/152/3/63. S2CID 119289027.
  7. ^ a b Warner, Brian D. (July 2018). “Near-Earth Asteroid Lightcurve Analysis at CS3-Palmer Divide Station: 2018 January-April” (PDF). Minor Planet Bulletin. 45 (3): 248–256. Bibcode:2018MPBu…45..248W. ISSN 1052-8091. Archived from the original (PDF) on 13 April 2019. Retrieved 8 September 2021.
  8. ^ a b Carry, B.; Solano, E.; Eggl, S.; DeMeo, F. E. (April 2016). “Spectral properties of near-Earth and Mars-crossing asteroids using Sloan photometry”. Icarus. 268: 340–354. arXiv:1601.02087. Bibcode:2016Icar..268..340C. doi:10.1016/j.icarus.2015.12.047. S2CID 119258489.
  9. ^ a b c “LCDB Data for (172034)”. Asteroid Lightcurve Database (LCDB). Retrieved 8 September 2021.
  10. ^ a b c Sarli, Bruno Victorino; Tsuda, Yuichi (September 2017). “Hayabusa 2 extension plan: Asteroid selection and trajectory design”. Acta Astronautica. 138: 225–232. Bibcode:2017AcAau.138..225S. doi:10.1016/j.actaastro.2017.05.016.
  11. ^ “MPC/MPO/MPS Archive”. Minor Planet Center. Retrieved 22 September 2018.

Source: en.wikipedia.org