astro.wikisort.org - Asteroid

2008 AO₁₁₂ (also written 2008 AO112) is an Apollo near-Earth asteroid and potentially hazardous object.[2] It was discovered on 12 January 2008 by the Mount Lemmon Survey at an apparent magnitude of 21 using a 1.5-meter (59 in) reflecting telescope.[1] The asteroid was quickly lost and had an estimated diameter of 310 meters (1,020 ft).[3] On 25 June 2009, with an observation arc of only 1 day in January 2008, the asteroid had a 1 in 4 million chance of impacting Earth on that very day.[3] The virtual impactor had not been eliminated from the Sentry Risk Table by the day of the potential impact.

2008 AO₁₁₂

Discovery[1][2]
Discovered by	Mt. Lemmon Survey
Discovery date	12 January 2008
Designations
Designation	2008 AO112 2013 EM20
Minor planet category	NEO Apollo PHA[2]
Orbital characteristics[2]
Epoch 18 April 2013 (JD 2456400.5)
Uncertainty parameter 1[2]
Aphelion	1.808 AU (Q)
Perihelion	0.9352 AU (q)
Semi-major axis	1.372 AU (a)
Eccentricity	0.3182
Orbital period (sidereal)	1.61 yr
Mean anomaly	100.4° (M)
Inclination	8.359°
Longitude of ascending node	73.98°
Argument of perihelion	350.0°
Physical characteristics
Dimensions	~310 meters (1,020 ft)[3]
Mass	4.1×1010 kg (assumed)[3]
Absolute magnitude (H)	19.9[2]

The asteroid was recovered on 5 March 2013 as 2013 EM₂₀.[4] Precovery images from 7 April 1997 at Kitt Peak National Observatory were located.[2] It was removed from the Sentry Risk Table on 30 March 2013.[5] It is now known that on 25 June 2009 the asteroid was 1.45 AU from Earth.[6]

References

External links

• 2008 AO112 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
• 2008 AO112 at ESA–space situational awareness
  • Ephemerides · Observations · Orbit · Physical Properties · Summary
• 2008 AO112 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters

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