J. Veverka, P. Thomas, A. Harch, B. Clark, J. F. Bell III, B. Carcich, J. Joseph, C. Chapman, W. Merline, M. Robinson, M. Malin, L. A. McFadden, S. Murchie, S. E. Hawkins III, R. Farquhar, N. Izenberg, A. Cheng

On 27 June 1997, the Near Earth Asteroid Rendezvous (NEAR) spacecraft flew within 1212 kilometers of asteroid 253 Mathilde. Mathilde is an irregular, heavily cratered body measuring 66 kilometers by 48 kilometers by 46 kilometers. The asteroid's surface is dark (estimated albedo between 0.035 and 0.050) and similar in color to some CM carbonaceous chondrites. No albedo or color variations were detected. The volume derived from the images and the mass from Doppler tracking of the spacecraft yield a mean density of 1.3 ± 0.2 grams per cubic centimeter, about half that of CM chondrites, indicating a porous interior structure.

J. Veverka, P. Thomas, A. Harch, B. Clark, J. F. Bell III, B. Carcich, J. Joseph, Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853, USA.
C. Chapman and W. Merline, Southwest Research Institute, 1050 Walnut Street, Suite 426, Boulder, CO 80302, USA.
M. Robinson, Department of Geological Sciences, Northwestern University, Evanston, IL 60208, USA.
M. Malin, Malin Space Science Systems, Post Office Box 910148, San Diego, CA 92191-0148, USA.
L. A. McFadden, Department of Astronomy, University of Maryland, College Park, MD 20742, USA.
S. Murchie, S. E. Hawkins III, R. Farquhar, N. Izenberg, A. Cheng, Applied Physics Laboratory, Johns Hopkins University, Laurel, MD 20723, USA.