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Updated: Jun 26, 2025
10:35
Bringing the Visible Universe into Focus with Robo-AO
Published on: February 12, 2013
19.5K
Cosmic dust impacts on the Hubble Space Telescope.
A T Kearsley1,2, R P Webb3, G W Grime3
1Science Innovation Platforms, Natural History Museum , London SW7 5BD, UK.
Summary
Hubble Space Telescope impacts reveal cosmic dust dominates over orbital debris for larger particles. Analysis of returned hardware shows micrometeoroids, not debris, caused most significant hypervelocity impacts.
Area of Science:
- Space Science
- Planetary Science
- Materials Science
Background:
- Hubble Space Telescope solar arrays and camera radiator shield experienced hypervelocity impacts.
- Returned hardware provides unique opportunity to study impact residues.
Purpose of the Study:
- Analyze composition and origin of larger impact features on returned Hubble components.
- Re-evaluate the ratio of micrometeoroid to orbital debris impacts.
Main Methods:
- Microscopic analysis (electron, ion, X-ray fluorescence) of impact sites.
- Laboratory experiments to validate impactor analysis.
- Comparison with existing orbital debris and micrometeoroid models.
Main Results:
- Majority (~90%) of impacts >50 μm were micrometeoroids (silicates, iron-nickel, spinel).
- Composition suggests asteroid origin for micrometeoroid impacts.
- Fewer large orbital debris impacts than predicted by NASA ORDEM and ESA MASTER models.
Conclusions:
- Micrometeoroids are the primary source of larger hypervelocity impacts on low Earth orbit spacecraft.
- Current orbital debris models may overestimate debris flux and underestimate micrometeoroid flux.
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