REDEFINING THE SOLAR RADIUS
Besselian Elements Team
Your guide to Solar Eclipses

2026 Eclipse Map
Display local circumstances computed using the IQP eclipse computational method that accounts for both the lunar limb, observer site topography, and it relies on an improved value for the eclipse solar radius (i.e. 959.95")

Eclipse App
Download our Countdown App to plan and observe your next eclipses powered by the most accurate computational method

Solar Radius Calculation
Read about our misson to determine the best solar radius value for eclipse computations by analyzing the flash spectrum, especially from the path edge. This improves eclipse maps and predictions
Who we are
We are the Besselian Elements Team, passionate eclipse chasers and researchers. We provide accurate eclipse calculations and share our work studying these awe-inspiring phenomena

Re-Entrant Totality
June 21, 2025
Is it possible for totality to be disrupted? The common understanding of total solar eclipses is that when the eclipse becomes total at second contact, ...
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Flash Spectrum video analysis with Python
July 6, 2024
Capturing the flash spectrum during a solar eclipse offers invaluable insights into the Sun’s outer layers like the chromosphere and the mesosphere. To harness this ...
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Flash Spectrum Recording Guidelines
May 25, 2024
Capturing the flash spectrum during a solar eclipse, with not professional equipment, is as challenging as it is rewarding. To help you get the best results, we’ve compiled a ...
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