Fig. 1

TES-derived global Lambert albedo of Mars (Christensen et al. 2001). Bright regions are covered by dust up to 2 m in thickness with particles in the size range of 2–40 μm. Dark regions are relatively dust-free but are dominated by particles 0.1 mm to 1 cm, rather than bedrock (Ruff and Christensen 2002*) (NASA/JPL/ASU)