Didymos

eccentricity

.3831233242624545 ± 1.0416E-10

semi-major axis

1.642709608529702 au ± 9.9148E-11

perihelion distance

1.013349242511927 au ± 1.733E-10

inclination; angle with respect to x-y ecliptic plane

3.413876519313629 deg ± 1.482E-8

longitude of the ascending node

72.9858236207145 deg ± 1.9715E-7

argument of perihelion

319.5807001349104 deg ± 2.1543E-7

mean anomaly

260.8612886320632 deg ± 7.0015E-8

time of perihelion passage

2461412.277780167719 TDB ± 1.6738E-7

sidereal orbital period

769.0235207660371 d ± 6.9623E-8

mean motion

.4681261239466357 deg/d ± 4.2381E-11

aphelion distance

2.272069974547477 au ± 1.3713E-10

absolute magnitude

18.11

diameter

0.78 km ± 0.03

extent

0.797 x 0.783 x 0.761 km ± 6% x 6% x 10%

bulk density

2.17 g/cm^3 ± 0.35

rotation period

2.2593 h

pole direction

78, -71 degrees ± 20 degrees

SMASSII spectral type

S

Published JPL orbital elements describe their stated epoch; they are not current positions. Small-body diameters can be effective/model-dependent sizes, not spherical shapes. Missing measurements remain unavailable. Pluto’s diameter uses the New Horizons reference rather than an empty SBDB field. Orbital epoch: JD 2461200.5 TDB.