Observing basics
天顶每小时流量
ZHR
The theoretical hourly rate of a shower under perfect skies.
You see 30–60% of ZHR depending on how high the radiant is.
Related terms
- Bortle scale — A 1–9 scale describing how dark a night sky is.
- Magnitude — A logarithmic brightness scale: smaller numbers are brighter.
- Limiting magnitude — The faintest magnitude visible under current conditions.
- Apparent magnitude — Brightness as seen from Earth, not intrinsic output.