2012 KT42

2012 KT₄₂

Designations
Minor planet category	Apollo NEO
Orbital characteristics
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 5
Aphelion	2.4839 AU (371.59 Gm)
Perihelion	0.71144 AU (106.430 Gm)
Periastron	94.628°
Semi-major axis	1.5977 AU (239.01 Gm)
Eccentricity	0.55470
Orbital period (sidereal)	2.02 yr (737.60 d)
Mean anomaly	261.31°
Mean motion	0° 29m 17.052s / day
Inclination	2.1932°
Longitude of ascending node	69.515°
Argument of perihelion	259.13°
Earth MOID	0.000968708 AU (144,916.7 km)
Physical characteristics
Dimensions	~4–10 metres
Synodic rotation period	0.06057 h (3.634 min)
Absolute magnitude (H)	29 29.0

2012 KT₄₂ is an Apollo near-Earth asteroid first observed by astronomer Alex R. Gibbs of the Mount Lemmon Survey with a 1.5-meter reflecting telescope on 28 May 2012.

Overview

The asteroid had a close approach to the Earth on 29 May 2012, approaching to only ~8950 miles (~14,440 km) above the planet's surface. This means 2012 KT₄₂ came inside the Clarke Belt of geosynchronous satellites. In May 2012, the estimated 5- to 10-metre-wide asteroid ranked #6 on the top 20 list of closest-approaches to Earth. There was no danger of a collision during the close approach. 2012 KT₄₂ passed roughly 0.01 AU (1,500,000 km; 930,000 mi) from Venus on 8 July 2012.

It is estimated that an impact would produce an upper atmosphere air burst equivalent to 11 kt TNT, roughly equal to Hiroshima's Little Boy. The asteroid would be vaporized as these small impacts occur approximately once per year. A comparable-sized object caused the Sutter's Mill meteorite in California on 2 April 2012. It was removed from the Sentry Risk Table on 30 May 2012.

External links

• JPL Small-Body Database Browser for 2012 KT42
• 2012 KT42 - Close Approach (Remanzacco Observatory in Italy)
• Images from Flyby (spaceweather.com)
• MPEC 2012-K66 : 2012 KT42 (Minor Planet Center Discovery announcement)
• Planetary Defense Blog post on 2012 KT42
• Video: Tiny Asteroid 2012 KT42 Crossing The Sky (universetoday 29 May 2012)
• The Peculiar Flyby of Asteroid 2012 KT42 (Pasquale Tricarico : 29 May 2012)
• 2012 KT42 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemerides · Observation prediction · Orbital info · MOID · Proper elements · Observational info · Close approaches · Physical info · Orbit animation
• 2012 KT42 at ESA–space situational awareness
  • Ephemerides · Observations · Orbit · Physical properties · Summary
• 2012 KT42 at the JPL Small-Body Database