(85182) 1991 AQ
| Discovery[1] | |
|---|---|
| Discovered by | E. F. Helin |
| Discovery site | Palomar Obs. |
| Discovery date | 14 January 1991 |
| Designations | |
| (85182) 1991 AQ | |
| 1991 AQ · 1994 RD | |
| Apollo · NEO · PHA[1][2] | |
| Orbital characteristics[2] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 26.91 yr (9,829 d) |
| Aphelion | 3.9474 AU |
| Perihelion | 0.4960 AU |
| 2.2217 AU | |
| Eccentricity | 0.7768 |
| 3.31 yr (1,210 d) | |
| 64.916° | |
| 0° 17m 51.36s / day | |
| Inclination | 3.1276° |
| 339.68° | |
| 242.96° | |
| Earth MOID | 0.0165 AU (6.428 LD) |
| Physical characteristics | |
| 1.1 km[3] 1.14 km (derived)[4] | |
| 0.18 (assumed)[4] 0.242±0.194[3] | |
| Q (Tholen)[4] | |
| 17.1[2] 17.20[4] | |
(85182) 1991 AQ (provisional designation 1991 AQ) is a stony asteroid on a highly eccentric orbit, classified as near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 1.1 kilometers (0.7 miles) in diameter. It was discovered on 14 January 1991, by American astronomer Eleanor Helin at the Palomar Observatory in California.[1] Based on its brightness variation of 0.69 magnitude, this Q-type asteroid is likely elongated.[4] It belongs to the small group of potentially hazardous asteroids larger than one kilometer.
Orbit and classification
[edit]1991 AQ is a member of the Earth-crossing class of Apollo asteroids, the largest group of near-Earth objects with approximately 10 thousand known members.[1][2] It is also a Venus- and Mars-crosser due to its extreme perihelion and aphelion, respectively.[2]
It orbits the Sun at a distance of 0.5–3.9 AU once every 3 years and 4 months (1,210 days; semi-major axis of 2.22 AU). Its orbit has a high eccentricity of 0.78 and an inclination of 3° with respect to the ecliptic.[2] The body's observation arc begins with its official discovery observation at Palomar in 1991.[1]
Close approaches
[edit]The asteroid has currently an Earth minimum orbital intersection distance of 0.0165 AU (2,470,000 km; 1,530,000 mi), which corresponds to 6.4 lunar distances and makes it a potentially hazardous asteroid due to its notably large size.[2] In 1991 and 1994, it approached Earth at a nominal distance of 0.054 AU (21 LD). The asteroids closest encounter with Earth is projected to occur on 27 January 2130, at a distance of 0.0106 AU (4.1 LD) only (see table).[5] It also makes close encounters to Mercury, Venus, Mars and Jupiter.[5]
| PHA | Date | Approach distance (lunar dist.) | Abs. mag (H) |
Diameter (C) (m) |
Ref (D) | ||
|---|---|---|---|---|---|---|---|
| Nomi- nal(B) |
Mini- mum |
Maxi- mum | |||||
| (33342) 1998 WT24 | 1908-12-16 | 3.542 | 3.537 | 3.547 | 17.9 | 556–1795 | data |
| (458732) 2011 MD5 | 1918-09-17 | 0.911 | 0.909 | 0.913 | 17.9 | 556–1795 | data |
| (7482) 1994 PC1 | 1933-01-17 | 2.927 | 2.927 | 2.928 | 16.8 | 749–1357 | data |
| 69230 Hermes | 1937-10-30 | 1.926 | 1.926 | 1.927 | 17.5 | 668–2158 | data |
| 69230 Hermes | 1942-04-26 | 1.651 | 1.651 | 1.651 | 17.5 | 668–2158 | data |
| (137108) 1999 AN10 | 1946-08-07 | 2.432 | 2.429 | 2.435 | 17.9 | 556–1795 | data |
| (33342) 1998 WT24 | 1956-12-16 | 3.523 | 3.523 | 3.523 | 17.9 | 556–1795 | data |
| (163243) 2002 FB3 | 1961-04-12 | 4.903 | 4.900 | 4.906 | 16.4 | 1669–1695 | data |
| (192642) 1999 RD32 | 1969-08-27 | 3.627 | 3.625 | 3.630 | 16.3 | 1161–3750 | data |
| (143651) 2003 QO104 | 1981-05-18 | 2.761 | 2.760 | 2.761 | 16.0 | 1333–4306 | data |
| 2017 CH1 | 1992-06-05 | 4.691 | 3.391 | 6.037 | 17.9 | 556–1795 | data |
| (170086) 2002 XR14 | 1995-06-24 | 4.259 | 4.259 | 4.260 | 18.0 | 531–1714 | data |
| (33342) 1998 WT24 | 2001-12-16 | 4.859 | 4.859 | 4.859 | 17.9 | 556–1795 | data |
| 4179 Toutatis | 2004-09-29 | 4.031 | 4.031 | 4.031 | 15.3 | 2440–2450 | data |
| 2014 JO25 | 2017-04-19 | 4.573 | 4.573 | 4.573 | 17.8 | 582–1879 | data |
| (137108) 1999 AN10 | 2027-08-07 | 1.014 | 1.010 | 1.019 | 17.9 | 556–1795 | data |
| (35396) 1997 XF11 | 2028-10-26 | 2.417 | 2.417 | 2.418 | 16.9 | 881–2845 | data |
| (154276) 2002 SY50 | 2071-10-30 | 3.415 | 3.412 | 3.418 | 17.6 | 714–1406 | data |
| (164121) 2003 YT1 | 2073-04-29 | 4.409 | 4.409 | 4.409 | 16.2 | 1167–2267 | data |
| (385343) 2002 LV | 2076-08-04 | 4.184 | 4.183 | 4.185 | 16.6 | 1011–3266 | data |
| (52768) 1998 OR2 | 2079-04-16 | 4.611 | 4.611 | 4.612 | 15.8 | 1462–4721 | data |
| (33342) 1998 WT24 | 2099-12-18 | 4.919 | 4.919 | 4.919 | 17.9 | 556–1795 | data |
| (85182) 1991 AQ | 2130-01-27 | 4.140 | 4.139 | 4.141 | 17.1 | 1100 | data |
| 314082 Dryope | 2186-07-16 | 3.709 | 2.996 | 4.786 | 17.5 | 668–2158 | data |
| (137126) 1999 CF9 | 2192-08-21 | 4.970 | 4.967 | 4.973 | 18.0 | 531–1714 | data |
| (290772) 2005 VC | 2198-05-05 | 1.951 | 1.791 | 2.134 | 17.6 | 638–2061 | data |
| (A) List includes near-Earth approaches of less than 5 lunar distances (LD) of objects with H brighter than 18. (B) Nominal geocentric distance from the Earth's center to the object's center (Earth radius≈0.017 LD). (C) Diameter: estimated, theoretical mean-diameter based on H and albedo range between X and Y. (D) Reference: data source from the JPL SBDB, with AU converted into LD (1 AU≈390 LD) (E) Color codes: unobserved at close approach observed during close approach upcoming approaches | |||||||
Physical characteristics
[edit]In the Tholen classification, this object is an uncommon Q-type asteroid, that falls into the larger stony S-complex.[4] As of 2018, no rotational lightcurve of this asteroid has been obtained from photometric observations. The body's rotation period, pole and shape remain unknown.[2] It has a brightness variation of 0.69 magnitude, indicative for an elongated, non-spherical shape.[4]
Diameter and albedo
[edit]According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, this asteroid measures 1.1 kilometers in diameter and its surface has an albedo of 0.242.[3] The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.18 and derives a diameter of 1.14 kilometers based on an absolute magnitude of 17.20.[4]
Numbering and naming
[edit]This minor planet was numbered by the Minor Planet Center on 30 August 2004 (M.P.C. 52517).[6] As of 2018, it has not been named.[1]
References
[edit]- ^ a b c d e f "85182 (1991 AQ)". Minor Planet Center. Retrieved 21 April 2018.
- ^ a b c d e f g h "JPL Small-Body Database Browser: 85182 (1991 AQ)" (2017-12-12 last obs.). Jet Propulsion Laboratory. Retrieved 21 April 2018.
- ^ 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.
- ^ a b c d e f g h "LCDB Data for (85182)". Asteroid Lightcurve Database (LCDB). Retrieved 21 April 2018.
- ^ a b "JPL Small-Body Database Browser: 85182 (1991 AQ)". Jet Propulsion Laboratory. Retrieved 21 April 2018.
- ^ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 21 April 2018.
External links
[edit]- List of the Potentially Hazardous Asteroids (PHAs), Minor Planet Center
- PHA Close Approaches To The Earth, Minor Planet Center
- Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- (85182) 1991 AQ at NeoDyS-2, Near Earth Objects—Dynamic Site
- (85182) 1991 AQ at ESA–space situational awareness
- (85182) 1991 AQ at the JPL Small-Body Database
