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Updated: Jul 18, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Organics captured from comet 81P/Wild 2 by the Stardust spacecraft.
Scott A Sandford1, Jérôme Aléon, Conel M O'd Alexander
1Astrophysics Branch, NASA-Ames Research Center, Moffett Field, CA 94035, USA. ssandford@mail.arc.nasa.gov
Science (New York, N.Y.)
|December 16, 2006
Summary
Comet 81P/Wild 2 samples reveal diverse organic compounds, some with interstellar origins. These extraterrestrial organics show unique compositions, differing from meteorites and interplanetary dust.
Area of Science:
- Cosmochemistry
- Astrobiology
- Planetary Science
Background:
- Cometary samples provide insights into the early solar system's chemical inventory.
- Understanding the composition of cometary organics is crucial for astrobiology and the origins of life.
Purpose of the Study:
- To characterize the organic composition of comet 81P/Wild 2 samples.
- To compare cometary organics with other extraterrestrial materials like meteorites and interplanetary dust particles.
- To investigate the potential heritage and formation pathways of these organic compounds.
Main Methods:
- Analysis of returned samples from comet 81P/Wild 2.
- Detailed chemical and isotopic analysis of organic molecules.
- Comparative analysis with existing databases of meteoritic and interplanetary dust organic compositions.
Main Results:
- Cometary organics exhibit heterogeneous distribution and unequilibrated composition.
- Organics are rich in oxygen and nitrogen, with lower aromatic content compared to meteorites and IDPs.
- Deuterium and nitrogen-15 excesses suggest interstellar/protostellar origins for some compounds.
- A distinct class of aromatic-poor organic material was identified.
Conclusions:
- Comet 81P/Wild 2 contains a diverse suite of identifiable organic compounds.
- These organics possess unique characteristics, including isotopic anomalies, pointing to complex formation histories.
- The findings contribute to understanding the delivery of prebiotic molecules to early Earth.
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