(458732) 2011 MD5

(458732) 2011 MD₅

Discovery [1] [2]
Discovered by	Pan-STARRS 1
Discovery site	Haleakala Obs.
Discovery date	30 June 2011
Designations
MPC designation	(458732) 2011 MD5
Alternative designations	2011 MD5
Minor planet category	NEO Apollo [2] [3]
Orbital characteristics [3]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 0
Observation arc	8.67 yr (3,165 d)
Aphelion	3.9869 AU
Perihelion	0.9895 AU
Semi-major axis	2.4882 AU
Eccentricity	0.6023
Orbital period (sidereal)	3.92 yr (1,434 d)
Mean anomaly	49.188°
Mean motion	0° 15m 3.96s / day
Inclination	10.553°
Longitude of ascending node	170.34°
Argument of perihelion	224.84°
Earth  MOID	0.0627 AU (24.4 LD)
Physical characteristics
Mean diameter	730–1600 m (CNEOS) [4] 0.8  km [5] 1.2  km
Absolute magnitude (H)	17.8 [3] 17.9 [2]

(458732) 2011 MD₅ is an Apollo near-Earth asteroid around 1.2 kilometers (0.75 miles) in diameter. It is the largest asteroid known to have passed closer than the Moon. ^[4] On 17 September 1918 the asteroid passed 0.00234 AU (350 thousand km; 0.91 LD) from Earth ^[3] with a peak apparent magnitude of around 8.4. The 1918 close approach distance is known with an accuracy of roughly ±120 km. The asteroid had come to opposition (opposite the Sun in the sky) on 9 August 1918 at magnitude 16.

2011 MD₅ was not discovered until 30 June 2011, ^[1] when the asteroid was 1.3  AU (190 million  km ) from Earth. As of 2023, the asteroid has a 12-year observation arc and a well determined orbit.

References

1. "MPEC 2011-N15 : 2011 MD5". IAU Minor Planet Center. 3 July 2011. Retrieved 14 June 2020. (K11M05D)
2. "458732 (2011 MD5)". Minor Planet Center. Retrieved 15 June 2020.
3. "JPL Small-Body Database Browser: 458732 (2011 MD5)". Jet Propulsion Laboratory. Archived from the original on 2 May 2020. Retrieved 14 June 2020.
4. NEO Earth Close Approaches Archived 19 October 2017 at the Wayback Machine @ JPL CNEOS
   Select "Nominal dist <= 1 LD", "Past only", Sort by "H (mag)"
5. "LCDB Data for (458732)". Asteroid Lightcurve Database (LCDB). Archived from the original on 15 June 2020. Retrieved 15 June 2020.

External links

• (458732) 2011 MD5 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemerides  · Observation prediction  · Orbital info  · MOID  · Proper elements  · Observational info  · Close approaches  · Physical info  · Orbit animation
• (458732) 2011 MD5 at ESA–space situational awareness
  • Ephemerides  · Observations  · Orbit  · Physical properties  · Summary
• (458732) 2011 MD5 at the JPL Small-Body Database
  • Close approach  · Discovery  · Ephemeris  · Orbit viewer  · Orbit parameters  · Physical parameters