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Updated: Jun 30, 2026

16:31
Echo Particle Image Velocimetry
Published on: December 27, 2012
Deimos encounter by viking: preliminary imaging results.
Summary
Viking flybys of Deimos revealed a cratered surface covered in regolith, boulders, and bright streaks, not a smooth, grooveless exterior as initially appeared. This regolith fill explains the moon's deceptively smooth appearance.
Area of Science:
- Planetary Science
- Geology
- Space Exploration
Background:
- Previous observations of Deimos suggested a smooth surface lacking geological features like grooves.
- Understanding the surface morphology of Deimos is crucial for comprehending its formation and evolution.
Purpose of the Study:
- To analyze the surface features of Deimos using high-resolution imagery from recent close flybys.
- To explain the apparent smoothness of Deimos's surface despite its cratered nature.
Main Methods:
- Analysis of high-resolution images obtained during close flybys of Deimos by the Viking spacecraft.
- Comparative study of surface features and their interpretation based on geological processes.
Main Results:
- Deimos's surface is covered with craters, contrary to initial observations.
- A layer of regolith fills smaller craters, contributing to an overall smooth appearance.
- The surface also exhibits boulders and bright, streak-like markings, potentially indicative of ejecta deposits.
Conclusions:
- The apparent smoothness of Deimos is an artifact of regolith fill in its craters.
- Surface features suggest geological activity or depositional processes, including the presence of boulders and ejecta-like streaks.
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