This page shows the Lewes weather forecast for the next 7 days, and the astronomical seeing conditions for tonight. In astronomy, seeing refers to the atmospheric conditions that affect the clarity of celestial objects we can see in the sky, particularly stars. Turbulence in the Earth's atmosphere causes starlight to twinkle, an undesirable effect in astronomy. Good seeing conditions allow clearer views through telescopes, with lower arc sec values indicating better seeing. To combat poor seeing, professional ground-based telescopes employ adaptive optics. Space telescopes like Hubble and James Webb operate beyond the atmosphere, hence they are unaffected by seeing issues.