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Updated: Jun 21, 2026
10:28
Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
H2O at the Phoenix landing site
P H Smith1, L K Tamppari, R E Arvidson
1Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA. psmith@lpl.arizona.edu
Science (New York, N.Y.)
|July 4, 2009
Summary
The Phoenix mission found shallow ice and alkaline soil on Mars. This suggests water was present, supporting the potential for past or present Martian habitability.
Area of Science:
- Planetary Science
- Astrobiology
- Mars Geology
Background:
- The Phoenix mission aimed to study Martian arctic geology and weather.
- Previous missions hinted at water ice on Mars, but direct shallow subsurface investigation was needed.
Purpose of the Study:
- To investigate patterned ground and weather in Mars' northern arctic region.
- To determine the composition and state of the shallow subsurface ice and soil.
Main Methods:
- Robotic arm excavation of Martian soil.
- Analysis of soil composition, including minerals and salts.
- Observation of surface frost and snowfall patterns.
Main Results:
- A shallow ice table was discovered at depths of 5-18 cm.
- The Martian soil was alkaline (pH 7.7) with calcium carbonate and other minerals.
- Water-ice frost and snowfall were observed interacting with the soil.
Conclusions:
- The presence of shallow ice and alkaline soil indicates past water activity.
- These findings support the potential for habitability in the Martian arctic.
- The interaction of water ice with soil is crucial for understanding Martian environmental processes.
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