Sailing Stones

Photo credit: Public Domain

In Death Valley, California, large rocks have left trails behind them as if they are sailing across the desert of their own volition. For centuries, folks have wondered at the strange phenomenon before scientists tracked the stones and discovered that they are moved by some pretty simple weather patterns—rocks are moved by rare occurrences of rainfall, which turns to ice at night, and melts during the day. A combination of this slick melting ice and a particularly slimy cyanobacteria that live in the soil, surface winds push these stones along the surface, leaving their signature traces.

Guiding Questions

  • What causes stones to sail?
  • What weather phenomenon are necessary for this to happen?
  • Could we predict when stones are likely to move based on weather?


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Cross-cutting Concepts

  • C1: Patterns
  • C2: Cause and Effect

Disciplinary Core Ideas

  • ESS2.D: Weather & Climate
  • PS2.A: Forces and Motion