Orbital bistatic radar observations of asteroid Vesta by the Dawn mission

Elizabeth M. Palmer, Essam Heggy, Wlodek Kofman

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

We present orbital bistatic radar observations of a small-body, acquired during occultation by the Dawn spacecraft at asteroid Vesta. The radar forward-scattering properties of different reflection sites are used to assess the textural properties of Vesta's surface at centimeter-to-decimeter scales and are compared to subsurface hydrogen concentrations observed by Dawn's Gamma Ray and Neutron Detector to assess potential volatile occurrence in the surface and shallow subsurface. We observe significant differences in surface radar reflectivity, implying substantial spatial variations in centimeter-to-decimeter-scale surface roughness. Our results suggest that unlike the Moon, Vesta's surface roughness variations cannot be explained by cratering processes only. In particular, the occurrence of heightened hydrogen concentrations within large smoother terrains (over hundreds of square kilometers) suggests that potential ground-ice presence may have contributed to the formation of Vesta's current surface texture. Our observations are consistent with geomorphological evidence of transient water flow from Dawn Framing Camera images.

Original languageEnglish
Article number409
JournalNature Communications
Volume8
Issue number1
DOIs
Publication statusPublished - 1 Dec 2017

Fingerprint

Vesta asteroid
Minor Planets
multistatic radar
Radar
Asteroids
radar tracking
orbitals
Hydrogen
Spacecraft
surface roughness
Surface Properties
Surface roughness
Gamma Rays
radar scattering
Neutrons
Ice
occurrences
framing cameras
Neutron detectors
Forward scattering

ASJC Scopus subject areas

  • Chemistry(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Physics and Astronomy(all)

Cite this

Orbital bistatic radar observations of asteroid Vesta by the Dawn mission. / Palmer, Elizabeth M.; Heggy, Essam; Kofman, Wlodek.

In: Nature Communications, Vol. 8, No. 1, 409, 01.12.2017.

Research output: Contribution to journalArticle

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