Published rates (ZHR) assume a perfect sky with the radiant overhead. Real rates are lower. Enter the shower's ZHR, how high the radiant is, your limiting magnitude and cloud cover for a realistic hourly estimate.
See our meteor shower pages for the radiant altitude in every state.
How it works
HR = ZHR × sin(h) ÷ r^(6.5 − LM) × (1 − clouds).
FAQ
What limiting magnitude do I have?
Dark rural skies ≈ 6.5; suburbs ≈ 5; cities ≈ 3–4. Convert SQM with the SQM-to-Bortle tool.
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