Localization and physical properties experiments conducted by Spirit at Gusev Crater

Area of Science:

• Planetary Science
• Mars Exploration
• Geology

Background:

• Understanding the Martian surface and environmental factors is crucial for rover operations and future exploration.
• The Spirit rover's mission involved extensive traverses and data collection on the Martian surface.

Purpose of the Study:

• To determine the precise location and relative elevation of the Spirit rover during its traverses.
• To investigate the physical properties of the Martian surface and their impact on rover performance, specifically solar cell output.

Main Methods:

• Bundle-adjusted retrievals using rover wheel turns, suspension, and tilt angles.
• Analysis of overlapping images for precise localization.
• Physical properties experiments to assess solar cell degradation and surface material characteristics.

Main Results:

• Accurate determination of Spirit's location and elevation from Columbia Memorial station to Bonneville crater.
• A daily decrease of 0.2% in solar cell output due to airborne dust deposition.
• Identification of cohesive soil-like deposits, rock coatings, and weak basaltic volcanic rocks.

Conclusions:

• The study successfully pinpointed the Spirit rover's position and elevation, providing valuable topographical data.
• Dust accumulation significantly impacted solar cell efficiency, a critical factor for rover longevity.
• The diverse geological materials and landforms encountered are products of volcanic, impact, aeolian, and water-related processes.