Observed arrival · 2026-10-25
The ridge keeps the sun for 50 minutes
Sunreach models when terrain blocks or reveals direct sunlight at a chosen outdoor viewpoint, with a 3D demo and an iPhone/iPad AR app in development.
- For
- Hikers and viewpoint planners
- Worth noticing
- Its Tunnel View example puts first direct light 50 minutes after sunrise, using a USGS ground model and a clear-sky calculation.
Field notes
The demo lets visitors choose a place and date, scrub through the day, and watch modeled mountain shadows move across terrain; the planned iPhone/iPad app adds an on-location camera overlay. At Yosemite’s Tunnel View, its 21 June 2027 example puts sunrise at 05:37 but direct light at the marked viewpoint at 06:27, with final direct light at 18:15. The estimate uses a USGS ground model and clear-sky geometry, with stated ±1-minute estimate plus atmospheric uncertainty.
Observed signals
Read the marks
Editorial observations of this landing page, not a rating.
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