NASA Color Trick Was Meant for Mars. Now It's Unveiling Rock Art on Earth
20 days ago
- Archaeologist Jon Harman discovered the decorrelation stretch technique, originally developed by NASA in 1978 to enhance satellite imagery, while attending a rock art conference in 2005.
- The technique, based on the Karhunen–Loève Transform, expands the color range to reveal hidden details, and Harman adapted it for rock art analysis using Ronald Alley's 1996 improved algorithm.
- Harman created the Dstretch software plug-in, which has uncovered previously invisible figures and details in ancient rock art across sites in Mexico, Egypt, Canada, and Norway.
- Applications include revealing bat and pig depictions in Egyptian tombs, a Crow warrior's pictograph in Canada, and new figures at Norway's Årsand 1 site, deepening understanding of ancient symbolic practices.