Satrelle - Eclipse Planner

On August 12, 2026, the moon's shadow crosses Spain at more than two thousand kilometers per hour. Satrelle tells you exactly when it reaches the spot where you're standing, to the second, computed on your phone, no signal required.

FREE, A COMPLETE OBSERVER'S TOOL

• Contact times C1-C4 for your exact position, from NASA Besselian elements, computed entirely on-device
• Totality duration, sun altitude, and a live countdown
• Set your site by GPS, on the map, or by typing coordinates
• The 2026 and 2027 eclipses, plus future events
• Works fully offline, in a field, on a mountain, anywhere

THE PHOTOGRAPHER'S KIT, ONE PURCHASE, YOURS FOREVER

Everything you use with a camera in your hands:

• Exposure toolkit, Espenak tables computed for your aperture, ISO, and filter, with live atmospheric extinction for your sun altitude
• Corona-pass fit, how many full bracket ladders your totality holds
• Eclipse-day mode, timed voice callouts, camera-filter warnings, and T-minus haptics through all four contacts
• Live Activity, the countdown on your lock screen and Dynamic Island
• Rehearsal mode, practice your totality before you spend it
• Site comparison, save candidate sites and compare their durations
• Clock verification against NTP, contact times ride on your clock
• Manual contact times from any limb-corrected site prediction

The Kit is a single one-time purchase. It includes the August 2027 eclipse and every eclipse after it, it's shareable with your family, and every feature works with no connection at all.

SAFETY

Never look at the sun without ISO 12312-2 eclipse glasses. The only exception is totality itself, between second and third contact, and Satrelle tells you exactly when that is.