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Updated: Jul 12, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
First images of asteroid 243 ida.
Science (New York, N.Y.)
|September 9, 1994
Summary
The Galileo mission revealed asteroid 243 Ida, a 56km irregular body with diverse geological features. Its ancient surface suggests a minimum age of 1 billion years for the Koronis family.
Area of Science:
- Planetary Science
- Asteroid Geology
- Space Exploration
Background:
- The Galileo spacecraft provided the first close-up images of the asteroid 243 Ida.
- Asteroid Ida is an irregular object with dimensions of 56x24x21 kilometers.
- Ida belongs to the Koronis family of asteroids.
Purpose of the Study:
- To analyze the geological features and surface characteristics of asteroid 243 Ida.
- To determine the surface age and cratering equilibrium of Ida.
- To infer the age of the Koronis asteroid family.
Main Methods:
- Analysis of high-resolution images from the Galileo spacecraft.
- Geological feature mapping, including grooves, blocks, chutes, and albedo variations.
- Crater morphology and size-frequency distribution analysis.
Main Results:
- Ida's surface exhibits a rich array of geological features: grooves, blocks, chutes, albedo variations, crater chains, and diverse crater morphologies.
- Nonuniform distribution of large blocks and preferential locations for lineaments and dark-floored craters were observed.
- A substantial regolith layer is inferred, with high crater density indicating saturation cratering equilibrium.
Conclusions:
- The surface of asteroid 243 Ida is geologically complex and ancient.
- The cratering density suggests a surface in equilibrium, supporting an estimated minimum age of 1 billion years for Ida.
- This age provides a minimum age estimate for the Koronis asteroid family, which is older than previously anticipated.
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