CaltechAUTHORS
Published October 2021 | Version Published
Journal Article Open

Size and Shape of (11351) Leucus from Five Occultations

Creators

  • 1. ROR icon Southwest Research Institute
  • 2. ROR icon University of Colorado Boulder
  • 3. ROR icon Lowell Observatory
  • 4. ROR icon University of Hawaii at Manoa
  • 5. ROR icon California Institute of Technology
  • 6. ROR icon The University of Texas at San Antonio
  • 7. ROR icon University of Arizona
  • 8. ROR icon University of Southern Queensland
  • 9. ROR icon University of Wyoming
  • 10. ROR icon NOIRLab
  • 11. ROR icon Search for Extraterrestrial Intelligence
  • 12. ROR icon Planetary Science Institute
  • 13. ROR icon Massachusetts Institute of Technology
  • 14. ROR icon University of Virginia

Abstract

We present observations of five stellar occultations for (11351) Leucus and reports from two efforts on (21900) Orus. Both objects are prime mission candidate targets for the Lucy Discovery mission. Combined results for Leucus indicate a very dark surface with p_V = 0.037 ± 0.001, which is derived from the average of the multichord occultations. Our estimate of the triaxial ellipsoidal shape is for axial diameters of 63.8 × 36.6 × 29.6 km assuming that the spin pole is normal to the line of sight. The actual shape of the object is only roughly elliptical in profile at each epoch. Significant topography is seen with horizontal scales up to 30 km and vertical scales up to 5 km. The most significant feature is a large depression on the southern end of the object as seen from a terrestrial viewpoint. For this work we developed a method to correct for differential refraction, accounting for the difference in color between the target object and the reference stars for astrometry derived from ground-based images.

Additional Information

© 2021. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Received 2020 June 8; revised 2021 August 2; accepted 2021 August 3; published 2021 September 24. This work was largely supported by the Lucy Mission, which is funded through the NASA Discovery program on contract No. NNM16AA08C. Funding for RECON was provided by grants from NSF AST-1413287, AST-1413072, AST-1848621, and AST-1212159. Funding for F. Marchis was provided by a grant from NSF AST-1743015. Pan-STARRS is supported by the National Aeronautics and Space Administration under grant No. 80NSSC18K0971 issued through the SSO Near Earth Object Observations Program. The Pan-STARRS1 Surveys (PS1) and the PS1 public science archive have been made possible through contributions by the Institute for Astronomy, the University of Hawaii, the Pan-STARRS Project Office, the Max-Planck Society and its participating institutes, the Max Planck Institute for Astronomy, Heidelberg, and the Max Planck Institute for Extraterrestrial Physics, Garching, Johns Hopkins University, Durham University, the University of Edinburgh, the Queen's University Belfast, the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Telescope Network Incorporated, the National Central University of Taiwan, the Space Telescope Science Institute, the National Aeronautics and Space Administration under grant No. NNX08AR22G issued through the Planetary Science Division of the NASA Science Mission Directorate, the National Science Foundation grant No. AST-1238877, the University of Maryland, Eotvos Lorand University (ELTE), the Los Alamos National Laboratory, and the Gordon and Betty Moore Foundation. Thanks to all our other essential contributors for the observing campaigns: Scott Adams, Seth Anthony, Teri Ast, David Barrows, Becky Bobick, Dick Bobick, Bill Boynton, Jesus Bustos, Brian E. Cain, Rene Cardenas, Catalina Chapman, Nina Chevalier, John G. Compton, Dorey W. Conway, Kenneth B. Conway, Richard L. Cunningham, Chris Erickson, Robert Ewing, Paul S. Facuna, Rick E. Frankenberger, Corbin Fredland, Phylis L. Hanna, Hugh C. Harris, Ryuga Hatano, Kevin R. Healy, Frances Healy, Jonathan Jacob Hernandez, Mark Hickinbotham, Tyler Frederick Hilgendorf, Bekah Hillard, Kimberly Jeanine Hollingsworth, Sam F. Insana, Robert A. Jones, Richard L. Karohl, Jim Kochenderfer, Christopher Koers, Kevin R. Kotara, Svitlana Kroll, Arnaud Malvache, Laurent Marfisi, Alexis Martin, Keitha McCandless, Mel E. McClure, Randy McKnight, Chuck McPartlin, Randle L. Mellen, Terry R. Miller, Crystal Moczygemba, Rod G. Moorehead, Sean Moss, Juan Munoz, Olivia Newton, Nidhi R Patel, Anthony J. Pistilli, Ryan Rickerson, Matthew Riehle, Susan K. Rost, Jack Rost, Eric Sahr, Jade Salazar, Ramsey Schar, Jim Scotti, Tiffany Severson, Myron Smith, Maria Stothoff, Stuart A. Stothoff, Emma Tibay, Kimberly Valenzuela, Kathryn Volk, Dannie Wayne Wagoner, Michelle Wilkinson, William Wilkinson, Robert P. Williams, Peggy Yeargain, Michael K. Young, and Amanda M. Zangari.

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Additional details

Identifiers

Eprint ID
111318
Resolver ID
CaltechAUTHORS:20211008-224616285

Funding

NASA
NNM16AA08C
NSF
AST-1413287
NSF
AST-1413072
NSF
AST-1848621
NSF
AST-1212159
NSF
AST-1743015
NASA
80NSSC18K0971
NASA
NNX08AR22G
NSF
AST-1238877
Gordon and Betty Moore Foundation

Dates

Created
2021-10-12
Created from EPrint's datestamp field
Updated
2021-10-12
Created from EPrint's last_modified field

Caltech Custom Metadata

Caltech groups
Division of Geological and Planetary Sciences (GPS)