2021 AV7 is a near-Earth asteroid of the Apollo group, discovered by astronomers Alain Maury and G. Attard at San Pedro de Atacama, Chile on 15 January 2021. With an estimated diameter of 440–1,000 m (1,440–3,280 ft), it is considered a potentially hazardous asteroid. It has a highly elliptical orbit that brings it within Earth's orbit. However, its nominal orbit has a minimum orbit intersection distance around 2.6×106 km (1.6×106 mi) from Earth's orbital path, and the closest approach the asteroid is expected to make over the next two centuries is to within 0.140 astronomical units (20.9×106 km; 13.0×106 mi) on 28 February 2096.[4]
| Discovery [1][2] | |
|---|---|
| Discovered by | AMACS1 (W94) Alain Maury G. Attard |
| Discovery site | San Pedro de Atacama |
| Discovery date | 15 January 2021 (first observed) |
| Designations | |
| 2021 AV7 | |
| 11E401 [3] | |
| NEO · Apollo · PHA [4] | |
| Orbital characteristics [4] | |
| Epoch 17 October 2024 (JD 2460600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 5.08 yr (1,857 days) |
| Aphelion | 5.232 AU |
| Perihelion | 0.9124 AU |
| 3.072 AU | |
| Eccentricity | 0.70300 |
| 5.38 yr | |
| 236.416° | |
| 0° 10m 58.964s / day | |
| Inclination | 28.4975° |
| 153.147° | |
| 7 April 2021 03:28 UT [4] | |
| 39.667° | |
| Earth MOID | 0.01756 AU (2,627,000 km) |
| Jupiter MOID | 0.78236 AU (117,039,000 km) |
| TJupiter | 2.650 |
| Physical characteristics | |
| 0.44–1.00 km (assumed albedo 0.05–0.25)[5] | |
| 20.0 (April 2021)[6] 19.8 (at discovery)[1] | |
| 18.93[4][2] | |
Discovery
edit2021 AV7 was discovered by astronomers Alain Maury and G. Attard at San Pedro de Atacama, Chile on 15 January 2021. It was first observed in the constellation Canis Major at an apparent magnitude of 19.8.[1] The asteroid was moving at an on-sky rate of 1.15 arcseconds per minute, from a distance of 0.656 AU (98.1 million km; 61.0 million mi) from Earth.[7]
The asteroid was subsequently listed on the Minor Planet Center's Near-Earth Object Confirmation Page (NEOCP) as 11E401.[3] Over three days, follow-up observations were carried out by various observatories including Spacewatch (691) at Kitt Peak and the Steward Observatory (I52) at Mount Lemmon. The listing was confirmed and publicly announced as 2021 AV7 on 18 January 2021.[1]
Orbit and classification
edit
With a long observation arc spanning over five years, the orbit of 2021 AV7 is well-secured with a condition code of 0.[4] The earliest known precovery observations of 2021 AV7 are from Pan-STARRS 1 on 9 July 2016. These precovery observations were published by the Minor Planet Center on 30 April 2021.[8]
2021 AV7 orbits the Sun at an average distance of 3.07 AU once every 5.38 years. Its orbit has a high eccentricity of 0.7 and an inclination of 28° with respect to the ecliptic plane. Over the course of its orbit, its distance from the Sun ranges from 0.91 AU at perihelion to 5.2 AU at aphelion, crossing the orbits of Earth, Mars, and Jupiter.[4] Since its orbit crosses that of Earth's while having a semi-major axis greater than 1 AU, 2021 AV7 is classified as an Apollo asteroid. Its nominal orbit has a minimum orbit intersection distance around 2.6×106 km (1.6×106 mi) from Earth's orbital path. Its closest recent approach to Earth occurred on 17 March 2021, at a distance of 0.276 AU (41.3 million km; 25.7 million mi), and the closest approach it is expected to make over the next two centuries is to within 0.140 AU (20.9 million km; 13.0 million mi) on 28 February 2096.[4]
Physical characteristics
editDiameter and albedo
editBased on an magnitude-to-diameter conversion and a measured absolute magnitude of 18.9, 2021 AV7 measures between 440 and 1,000 meters in diameter for an assumed geometric albedo of 0.25 and 0.05, respectively.[2][5]
References
edit- ^ a b c d "MPEC 2021-B45 : 2021 AV7". Minor Planet Electronic Circular. Minor Planet Center. 18 January 2021. Retrieved 19 January 2021.
- ^ a b c "2021 AV7". Minor Planet Center. International Astronomical Union. Retrieved 19 January 2021.
- ^ a b "2021 AV7". NEO Exchange. Las Cumbres Observatory. 18 January 2021. Retrieved 19 January 2021.
- ^ a b c d e f g h "JPL Small-Body Database Browser: 2021 AV7" (2021-08-09 last obs.). Jet Propulsion Laboratory. Retrieved 10 April 2021.
- ^ a b Bruton, Dan. "Conversion of Absolute Magnitude to Diameter for Minor Planets". Department of Physics, Engineering, and Astronomy. Stephen F. Austin State University. Archived from the original on 23 July 2011. Retrieved 19 January 2021.
- ^ "2021AV7". Near Earth Objects – Dynamic Site. Department of Mathematics, University of Pisa, Italy. Retrieved 19 January 2021.
- ^ "2021AV7 Ephemerides". Near Earth Objects – Dynamic Site (Ephemerides at discovery (obs. code W94)). Department of Mathematics, University of Pisa, Italy. Retrieved 19 January 2021.
- ^ "MPEC 2021-H152 : 2021 AV7". Minor Planet Electronic Circular. Minor Planet Center. 30 April 2021. Retrieved 6 May 2021.
External links
edit- MAP program discoveries, Alain Maury, San Pedro de Atacama Celestial Explorations, 10 February 2021
- 2021 AV7 at NeoDyS-2, Near Earth Objects—Dynamic Site
- 2021 AV7 at ESA–space situational awareness
- 2021 AV7 at the JPL Small-Body Database
