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Updated: Jul 18, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Infrared spectroscopy of comet 81P/Wild 2 samples returned by Stardust.
Lindsay P Keller1, Sasa Bajt, Giuseppe A Baratta
1Astromaterials Research and Exploration Science Directorate, Mail Code KR, NASA-Johnson Space Center, Houston, TX 77058, USA. lindsay.p.keller@nasa.gov
Science (New York, N.Y.)
|December 16, 2006
Summary
Stardust mission samples from comet 81P/Wild 2 show long-chain aliphatic hydrocarbons and silicates, indicating a mix of solar system and interstellar matter. The absence of hydrous minerals suggests no water processing occurred.
Area of Science:
- Cosmic Dust Analysis
- Cometary Science
- Astrochemistry
Background:
- Comets are key to understanding early solar system composition.
- Interplanetary dust particles (IDPs) provide pristine samples of extraterrestrial material.
- The Stardust mission collected samples directly from comet 81P/Wild 2.
Purpose of the Study:
- To analyze the mineralogical and chemical composition of comet 81P/Wild 2 samples.
- To investigate the origin and processing history of cometary materials.
- To compare cometary components with interstellar and solar system materials.
Main Methods:
- Infrared spectroscopy was used to analyze the captured cometary material.
- Mineralogical identification of silicates (amorphous and crystalline) and hydrocarbons.
- Comparison of spectral data with known interstellar and solar system compositions.
Main Results:
- Indigenous aliphatic hydrocarbons with longer chains than those in the interstellar medium were detected.
- Abundant amorphous and crystalline silicates (olivine, pyroxene) were identified.
- Absence of hydrous silicates and carbonate minerals, suggesting limited aqueous alteration.
Conclusions:
- Cometary dust contains a mixture of solar system and presolar interstellar matter.
- The detected hydrocarbons suggest unique formation pathways or processing in the comet.
- Comet 81P/Wild 2 likely experienced minimal aqueous alteration.
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