ICARUS 63, 201--205 (1985) Physical Parameters of Near-Earth Asteroid 1982 DV FAITH VILAS, 1 DAVID J. THOLEN, 2 LARRY A. LEBOFSKY, 3 AND HUMBERTO CAMPINS 3'4 Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721 GLENN J. VEEDER 3 Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 RICHARD P. BINZEL Department of Astronomy, University of Texas, Austin, Texas 78712 AND ALAN T. TOKUNAGA Institute for Astronomy, University of Hawaii, Honolulu, Hawaii 96822 Received November 19, 1984; revised May 20, 1985 Visual and infrared observations were made of Amor asteroid 1982 DV during its discovery apparition. Broadband visual and near-infrared photometry shows that it is an S-class asteroid. Narrowband spectrophotometry shows an absorption feature due to olivine or pyroxene or both centered at 0.93 gm. Applying a nonrotating thermal model to 10-/zm photometry, the geometric albedo is calculated to be approximately 0.27. The geometric albedo for a slowly rotating, rocky surface was calculated for 1 night to be 0.15, consistent with S-class asteroid albedos. Thus, 1982 DV is either one of the most reflective S-class asteroids known, or a significant amount of bare rock is exposed on the asteroid's surface. For the nonrotating model, ellipsoidal dimensions for 1982 DV are 3.5 × 1.4 × 1.4 km. © 1985AcademicPress. Inc. INTRODUCTION The known near-Earth asteroids repre- sent a population of objects which probably contains the sources of the meteorites found on the Earth. Additionally, their proximity to the Earth identifies them as attractive targets for future space explora- tion. Thus, determination of the physical ~ Present address: NASA Johnson Space Center/ SN3, Houston, Tex. 77058. 2 Present address: Institute for Astronomy, Univer- sity of Hawaii, Honolulu, Hawaii 96822. 3 Visiting astronomer at the Infrared Telescope Fa- cility, which is operated by the University of Hawaii under contract from the National Aeronautics and Space Administration. 4 Present address: Planetary Science Institute, 2030 E. Speedway, Suite 201, Tucson, Ariz. 85719. 201 properties of the near-Earth asteroids is of significant interest. The Amor asteroid 1982 DV was discovered by Schuster (1982) in February 1982. Helin et ai. (1984) report that 1982 DV is the ninth most accessible asteroid for rendevous by unmanned space probes. An effort was made to collect a va- riety of data on this asteroid during the fa- vorable apparition of 1982 in order to char- acterize its physical properties. We report some of these observations here. OBSERVATIONS Visual and near-infrared observations of 1982 DV were obtained at the University of Arizona Catalina Station 1.54-m telescope. Broadband photometry was obtained on UT May 15, 21, and 23, 1982, using a photome- 0019-1035/85 $3.00 Copyright © 1985by AcademicPress, Inc. All rights of reproduction in any form reserved.