2021 AV7

Summary

2021 AV7
Discovery [1][2]
Discovered byAMACS1 (W94)
Alain Maury
G. Attard
Discovery siteSan Pedro de Atacama
Discovery date15 January 2021 (first observed)
Designations
2021 AV7
11E401 [3]
NEO · Apollo · PHA[4]
Orbital characteristics[4]
Epoch 17 December 2021 (JD 2459200.5)
Uncertainty parameter 1 [4]
Observation arc4.81 yr (1,756 days)
Aphelion5.206 AU
Perihelion0.8976 AU
3.052 AU
Eccentricity0.70587
5.33 yr
339.452°
0° 11m 5.546s / day
Inclination29.400°
153.486°
7 April 2021 03:28 UT [4]
39.043°
Earth MOID0.00047 AU (70,000 km)
Jupiter MOID0.78459 AU (117,373,000 km)
TJupiter2.650
Physical characteristics
Mean diameter
0.44–1.00 km (assumed albedo 0.05–0.25)[5]
20.0 (April 2021)[6]
19.8 (at discovery)[1]
19.0±0.5[4]
19.0[2]

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 450–1,000 m (1,480–3,280 ft), it is considered a potentially hazardous asteroid. It has a highly elliptical orbit that brings it within Earth's orbit. Although its nominal orbit has a small minimum orbit intersection distance around 70,000 km (43,000 mi) from Earth's orbital path, the asteroid does not make any close approaches within 0.2 astronomical units (30×10^6 km; 19×10^6 mi) over the next 100 years.[4]

Discovery

2021 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

Orbit diagram of 2021 AV7, Jupiter, and the inner planets viewed from the ecliptic pole

With a long observation arc spanning over 4 years, the orbit of 2021 AV7 is well-secured with a condition code of 1.[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 3.05 AU once every 5.33 years. Its orbit has a high eccentricity of 0.71 and an inclination of 29° with respect to the ecliptic plane. Over the course of its orbit, its distance from the Sun ranges from 0.90 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. Although its nominal orbit has a small minimum orbit intersection distance around 0.00047 AU (70,000 km; 44,000 mi) from Earth's orbital path, the asteroid will not make any close approaches within 0.2 astronomical units (30×10^6 km; 19×10^6 mi) over the next 200 years.[4]

Physical characteristics

Diameter and albedo

Based 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

  1. ^ a b c d "MPEC 2021-B45 : 2021 AV7". Minor Planet Electronic Circular. Minor Planet Center. 18 January 2021. Retrieved 19 January 2021.
  2. ^ a b c "2021 AV7". Minor Planet Center. International Astronomical Union. Retrieved 19 January 2021.
  3. ^ a b "2021 AV7". NEO Exchange. Las Cumbres Observatory. 18 January 2021. Retrieved 19 January 2021.
  4. ^ a b c d e f g h i "JPL Small-Body Database Browser: 2021 AV7" (2021-03-25 last obs.). Jet Propulsion Laboratory. Retrieved 10 April 2021.
  5. ^ a b Bruton, Dan. "Conversion of Absolute Magnitude to Diameter for Minor Planets". Department of Physics, Engineering, and Astronomy. Stephen F. Austin State University. Retrieved 19 January 2021.
  6. ^ "2021AV7". Near Earth Objects – Dynamic Site. Department of Mathematics, University of Pisa, Italy. Retrieved 19 January 2021.
  7. ^ "2021AV7 Ephemerides". Near Earth Objects – Dynamic Site (Ephemerides at discovery (obs. code W94)). Department of Mathematics, University of Pisa, Italy. Retrieved 19 January 2021.
  8. ^ "MPEC 2021-H152 : 2021 AV7". Minor Planet Electronic Circular. Minor Planet Center. 30 April 2021. Retrieved 6 May 2021.

External links

  • MAP program discoveries, Alain Maury, San Pedro de Atacama Celestial Explorations, 10 February 2021
  • 2021 AV7 at NeoDyS-2, Near Earth Objects—Dynamic Site
    • Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
  • 2021 AV7 at ESA–space situational awareness
    • Ephemerides · Observations · Orbit · Physical Properties · Summary
  • 2021 AV7 at the JPL Small-Body Database
    • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters