(6178) 1986 DA

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(6178) 1986 DA
Discovery
Discovered by Minoru Kizawa
Discovery date February 16, 1986
Designations
Alternative names none
Minor planet
category
Amor asteroid
Epoch July 14, 2004 (JD 2453200.5)
Aphelion 666.686 Gm (4.457 AU)
Perihelion 173.713 Gm (1.161 AU)
Semi-major axis 420.199 Gm (2.809 AU)
Eccentricity 0.587
Orbital period 1719.466 d (4.71 a)
Average orbital speed 17.77 km/s
Mean anomaly 311.696°
Inclination 4.310°
Longitude of ascending node 64.795°
Argument of perihelion 127.171°
Physical characteristics
Dimensions 2.3 km 1
Mass ~2×1013 kg
Mean density 5 g/cm³
Equatorial surface gravity ? m/s²
Escape velocity ? km/s
Rotation period 0.149 d [1]
Albedo ~0.14
Temperature ~164 K
Spectral type M-type asteroid
Absolute magnitude 15.1

(6178) 1986 DA is a 2.3-kilometre-diameter M-type Mars-crosser and near-Earth asteroid, notable for being significantly more radar-reflective than other asteroids. It is an Amor asteroid, which means it approaches the orbit of Earth from the outside but does not cross it.

Radar measurements suggest it is composed of nickel and iron and that it was derived from the center of a much larger object that experienced melting and differentiation. The observed radar albedo was 0.58 and the optical albedo was 0.14.[1]

This asteroid was most likely formed from a larger body through a catastrophic collision with another object. Radar measurements of this body indicate that the surface is relatively smooth on scales of less than a meter, but it is highly irregular on scales of 10–100 meters.

The delta-v for a spacecraft rendezvous with this asteroid from low earth orbit is 7.1 km/s.[2].

1986 DA reached perihelion in its orbit on March 6, 2005.

[edit] References

  1. ^ 6178 (1986 DA) (NASA abstract)
  2. ^ Delta-v for spacecraft rendezvous with all known near-Earth asteroids. NASA (2006-06-01). Retrieved on 2006-06-08.