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Rotational Poles and Dimensions of Ceres and Vesta and three STEAs. Jack Drummond Starfire Optical Range Air Force Research Lab. Rotating 3x2x1 Asteroid. Fits are Made in the Fourier Plane. Image = E סּ L ₣ (Image) = K 0 2J 1 (x)/x. Juno Fit Diagnostics Shane 3 m at 2.1 μ m.
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Rotational Poles and Dimensions of Ceres and Vestaand three STEAs Jack Drummond Starfire Optical Range Air Force Research Lab
Fits are Made in the Fourier Plane Image = E סּ L ₣ (Image) = K0 2J1(x)/x
Ceres Dimensions This work Thomas et al a=b=α= 480±1 km 487.3±1.5 km c=[β2-a2 sin(θ)2]½ / cos(θ)= 448±1 km 454.7±1.5 km
Lightcurves HST SI AO
Weighted Mean Vesta This Work (n=4) Thomas et al a = 562±2 km 578±10 km b = 543±2 km 560±10 km c = 458±4 km 458±10 km RA = 325° 301° Dec= +55° +41° Error radius = 6.7° 5°
STEAs(Standard Triaxial Ellipsoid Asteroids) a Al Conrad, Bill Merline, Christophe Dumas, Drummond et al. 2007, Icarus in press: ‘Direct measurement of the size, shape, and pole of 511 Davida with Keck AO in a single night’ b Merline et al. 2007, In prep: ‘Direct measurement of the size, shape, and pole of 52 Europa with Keck AO in a single night’ c Drummond and Julian Christou 2007, Icarus submitted: ‘Triaxial Ellipsoid Dimensions and Rotational Poles of Seven Asteroids from Lick Observatory Adaptive Optics Images, and of Ceres’