astro.wikisort.org - Asteroid

(86039) 1999 NC₄₃, is an asteroid on an eccentric orbit, classified as near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 2 kilometers in diameter. This suspected tumbler and relatively slow rotator was discovered by LINEAR in 1999.[2]

(86039) 1999 NC₄₃

Discovery[1]
Discovered by	LINEAR
Discovery site	Lincoln Lab's ETS
Discovery date	14 July 1999
Designations
MPC designation	(86039) 1999 NC43
Alternative designations	1999 NC43
Minor planet category	Apollo · NEO · PHA[1][2]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	15.04 yr (5,492 days)
Aphelion	2.7785 AU
Perihelion	0.7400 AU
Semi-major axis	1.7593 AU
Eccentricity	0.5794
Orbital period (sidereal)	2.33 yr (852 days)
Mean anomaly	199.72°
Mean motion	0° 25m 20.64s / day
Inclination	7.1239°
Longitude of ascending node	311.76°
Argument of perihelion	120.61°
Earth MOID	0.0243 AU · 9.5 LD
Physical characteristics
Mean diameter	1.43±0.07 km[3] 2.22 km[4][5]
Synodic rotation period	34.29±0.06 h[6][7] 34.49±0.18 h[lower-alpha 1]
Geometric albedo	0.13[4] 0.14[5] 0.352±0.039[3]
Spectral type	SMASS = Q[1][8]
Absolute magnitude (H)	16.0[1][3] · 16.08[9] · 16.1[4][8]

Discovery

The asteroid was discovered on 14 July 1999, by the Lincoln Near-Earth Asteroid Research (LINEAR) team at Lincoln Laboratory's Experimental Test Site, near Socorro, New Mexico, USA, at an apparent magnitude of 18, using a 1.0-meter reflector.[2][10]

Its first observation was made by the Catalina Sky Survey in June 1999, extending the asteroid's observation arc by one month prior to its official discovery observation.[2]

Orbit and classification

1999 NC₄₃ has a well-determined orbit with an uncertainty of 0. The body orbits the Sun at a distance of 0.7–2.8 AU once every 2 years and 4 months (852 days). Its orbit has an eccentricity of 0.58 and an inclination of 7° with respect to the ecliptic.[1] Its Earth minimum orbit intersection distance is 0.0243 AU (3,640,000 km), which corresponds to 9.5 lunar distances. Its most notable close approach to Earth will be on 14 February 2173 at a distance of 0.03361 AU (5,028,000 km).[11] The asteroid also makes close approaches to Venus and Mars.

Physical characteristics

The rare Q-type asteroid is one of only 20 characterized bodies of this spectral type in the SMASS taxonomic scheme.[12]

Rotation period

Several rotational lightcurves were obtained from photometric observations by Czech astronomer Petr Pravec at Ondřejov Observatory and American astronomer Brian Warner at his private Palmer Divide Observatory, Colorado. Best rated results gave a rotation period of 34.49±0.18 hours with an exceptionally high brightness variation of 1.1 magnitude (U=n.a.).[lower-alpha 1] Pravec's alternative period of 122 hours was later not supported by Warner.[6] However, there are still other periods possible due to sparse photometric data points. The asteroid is also suspected to be in a tumbling motion, which makes the determination of its period more complex.[7] For an asteroid of its size, it is a relatively slow rotator.

Diameter and albedo

According to the survey carried out by the Japanese Akari satellite, the asteroid has a high albedo of 0.35 and a diameter of 1.43 kilometers.[3] Observations by the Keck Observatory in the thermal infrared gave a refined albedo of 0.13–0.14 with a larger diameter of 2.22 kilometers.[4][5][8]

Chelyabinsk meteor fragment

1999 NC₄₃ is suspected to be related to the 20-meter Chelyabinsk meteor, which exploded as a bright fireball over Russia on 15 February 2013. Analysis showed similar orbits for both bodies and suggested that they were once part of the same object.[13][14]

Numbering and naming

This minor planet was numbered by the Minor Planet Center on 30 August 2004.[15] As of 2018, it has not been named.[2]

Notes

References

External links

• Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
• Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
• (86039) 1999 NC43 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
• (86039) 1999 NC43 at ESA–space situational awareness
  • Ephemerides · Observations · Orbit · Physical Properties · Summary
• (86039) 1999 NC43 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters

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