Sky Conditions and Scales
Protect our night skies:
The International Dark-Sky Association – Non-profit organization fighting to preserve the night, protecting wildlife, cutting energy waste and stopping light pollution
Estimating Limiting Magnitude – by Nine Planets
Antoniadi Seeing Scale – Seeing scale used for planetary and lunar observing.
Clear Sky Chart – Find out what your sky conditions are in your area.
Mt. Wilson Solar Seeing Scale – Seeing conditions for solar observing.
Pickering Scale – Pickering scale of rating atmospheric turbulence, hosted by Damian Peach’s site.
PCW Memorial Observatory - Erika Rix 