(6178) 1986 DA

Infobox Planet | discovery=yes | physical_characteristics = yes | bgcolour=#FFFFC0
name=(6178) 1986 DA
discoverer=Minoru Kizawa
discovered=February 16, 1986
alt_names="none"
mp_category=Amor asteroid
epoch=July 14, 2004 (JD 2453200.5)
semimajor=420.199 Gm (2.809 AU)
perihelion=173.713 Gm (1.161 AU)
aphelion=666.686 Gm (4.457 AU)
eccentricity=0.587
period=1719.466 d (4.71 a)
inclination=4.310°
asc_node=64.795°
arg_peri=127.171°
mean_anomaly=311.696°
avg_speed=17.77 km/s
dimensions=2.3 km ^{[http://newton.dm.unipi.it/cgi-bin/neodys/neoibo?objects:1986DA;main 1]}
mass=~2×10¹³ kg
density=5 g/cm³
surface_grav=? m/s²
escape_velocity=? km/s
rotation=0.149 d [http://www.astrosurf.com/aude/map/us/AstFamilies2004-05-20.htm]
spectral_type=M-type asteroid
abs_magnitude=15.1
albedo=~0.14
single_temperature=~164 K

(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. [ [http://echo.jpl.nasa.gov/asteroids/1986da/1986DA.html 6178 (1986 DA)] (NASA abstract)]

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. [cite web | date = 2006-06-01 | url = http://echo.jpl.nasa.gov/~lance/delta_v/delta_v.rendezvous.html | title = Delta-v for spacecraft rendezvous with all known near-Earth asteroids | publisher = NASA | accessdate = 2006-06-08 ] .

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

References