Streaks on martian slopes are dry

Area of Science:

• Planetary Science
• Geology
• Astrobiology

Background:

• Slope streaks are dark albedo features on Martian slopes, historically attributed to aqueous processes.
• This attribution implied the presence of liquid water or brines, impacting assessments of Mars' habitability.

Purpose of the Study:

• To create a comprehensive global catalog of Martian slope streaks using a deep learning approach.
• To investigate the formation mechanisms of slope streaks and their role in Martian surface processes.

Main Methods:

• Utilized a deep learning-enabled approach for consistent, global cataloging of slope streaks.
• Conducted global geostatistical analysis to evaluate formation models.

Main Results:

• Generated a catalog of half a million individual slope streaks, modifying less than 0.1% of the Martian surface.
• Demonstrated that slope streaks transport significant amounts of dust, playing a role in the Martian dust cycle.
• Provided evidence supporting dry formation mechanisms over aqueous processes for slope streaks.

Conclusions:

• Martian slope streaks are primarily formed by dry processes, driven by dust delivery and energetic triggers.
• The findings challenge the hypothesis of widespread transient liquid water or brines on modern Martian slopes.
• Terrains with slope streaks can be explored without significant planetary protection concerns related to water-related habitability.