Near-Earth Asteroid Elongations from Radar Observations
Last modified: 2006 September 18
Pole-on elongations estimated from convex hulls, three-dimensional shape reconstructions, or
bandwidth extrema from observations that do not permit hull or shape inversions due to
insufficient SNR. For the non-principal axis rotator Toutatis, we list the ratio of the long
to the intermediate axis from its shape model. For objects described in more than one
paper, the most recent estimate of the elongation is cited (e.g., Castalia and Geographos).
Pole-on Inversion
Asteroid elongation method Reference
-------- ---------- --------- ---------
1620 Geographos 2.5 3-D model Hudson and Ostro 1999
11066 Sigurd 2.5 bandwidth extrema Benner et al. 2004
4179 Toutatis 2.4 3-D model Hudson and Ostro 1995
433 Eros 2.2 3-D, hull Mitchell et al. 1998, Ostro et al. 1990b
1627 Ivar 2.1 hull Ostro et al. 1990a
2063 Bacchus 2.1 3-D model Benner et al. 1999b
25143 Itokawa 1.9 3-D model Ostro et al., 2004, 2005
2005 CR37 1.9 bandwidth extrema Benner et al. 2006
4183 Cuno 1.7 bandwidth extrema Benner et al. 2001
4769 Castalia 1.6 3-D model Hudson and Ostro 1994
1685 Toro 1.5 ellipsoid fit Ostro et al. 1983
3103 Eger 1.5 bandwidth extrema Benner et al. 1997
10115 1992 SK 1.5 3-D model Busch et al. 2006
6178 1986 DA 1.4 hull Ostro et al. 1991
6489 Golevka 1.4 3-D model Hudson et al. 2000
1862 Apollo 1.3 hull Ostro et al., 2002
2100 Ra-Shalom 1.2 hull Shepard et al. 2000
3908 Nyx 1.2 hull, 3-D Benner et al. 2002b
4197 1982 TA 1.2 hull * unpublished *
7822 1991 CS 1.2 hull Benner et al. 1999a
66391 1999 KW4 1.2 3-D model (secondary) Ostro et al, submitted
1998 KY26 1.2 hull Ostro et al. 1999
1999 JM8 1.2 bandwidth extrema Benner et al., 2002a
1999 RQ36 1.2 3-D model Hudson et al. 2000
1998 ML14 1.1 3-D model Ostro et al. 2001
1580 Betulia 1.1 3-D model Magri et al, in press
100085 1992 UY4 1.1 bandwidth extremea Benner et al, in preparation
66391 1999 KW4 1.0 3-D model (primary) Ostro et al, submitted
2002 CE26 1.0 3-D model (primary) Shepard et al., 2006
N = 29
Mean and rms dispersion = 1.53 +/- 0.47
MANY other data sets are available that should yield hulls and/or 3-D reconstructions.
REFERENCES
----------
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