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Surface changes on comet 67P/Churyumov-Gerasimenko suggest a more active past
M Ramy El-Maarry1,2, O Groussin3, N Thomas4
1Physikalisches Institut, Universität Bern, 3012 Bern, Switzerland. mohamed.el-maarry@lasp.colorado.edu.
Science (New York, N.Y.)
|March 23, 2017
Summary
Rosetta spacecraft data reveals localized changes on comet 67P/Churyumov-Gerasimenko due to solar exposure. These minor surface alterations suggest major landforms formed early in the comet's history.
Area of Science:
- Cometary science
- Planetary geology
- Space exploration
Background:
- The Rosetta mission orbited comet 67P/Churyumov-Gerasimenko for approximately two years.
- Observations focused on surface characterization and monitoring at submeter scales.
Purpose of the Study:
- To analyze localized surface changes on comet 67P/Churyumov-Gerasimenko observed between December 2014 and June 2016.
- To understand the processes driving these changes and their implications for the comet's landscape evolution.
Main Methods:
- In-situ surface monitoring by the Rosetta spacecraft.
- Analysis of high-resolution imagery and data to identify and quantify surface changes.
- Attribution of observed changes to cometary weathering, erosion, and transient solar-driven events.
Main Results:
- Numerous localized surface changes were observed on comet 67P/Churyumov-Gerasimenko.
- These changes are attributed to cometary weathering, erosion, and transient events driven by solar exposure.
- Despite localized alterations, the overall scale of changes has not substantially modified the comet's major landforms.
Conclusions:
- The limited scale of recent changes suggests that the major landforms of comet 67P/Churyumov-Gerasimenko were established early in its current orbital configuration.
- The formation of these landforms may predate the current orbit, potentially linked to a larger inventory of volatiles like CO or CO2 ices, or amorphous ice.
- Compositional or physical heterogeneity is suggested by localized changes, but landscape evolution is primarily ancient.
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