StarsOut
Should you go outside tonight?
Great night tonight
Clear skies and dark conditions. Go outside.
Coimbra
7.7
out of 10
Low confidence
Models disagree on tonight — actual conditions may be cloudier.
Peak 2h
8.000:00–02:00
Prime 21–01
7.821:00–01:00
Best this week
7.2Fri, Jul 17
Moon
Waxing Crescent
5% lit
Moon doesn’t interfere — perfect darkness
🔭 Moon up: 08:34–22:38
Full moon: Jul 29
Sky now
Mostly cloudy · 75%
Measured at LPPR · 117km away · 18min ago
Sun ↓ 21:01·Dark from 22:01·77% clouds
Alert me on good nightsSky quality tonight
Best: 00:00–02:00This week’s nights
Europe/LisbonHow the score works
60% weight
Cloud cover
Layer-weighted across the best 2-hour window of the night. Low clouds block everything, thin high cirrus still lets bright stars through.
40% weight
Moon darkness
A new moon boosts the score. A full moon near midnight washes out all but the brightest stars. We ease the penalty after midnight when the moon is setting.