StarsOut
Should you go outside tonight?
Great night tonight
Clear skies and dark conditions. Go outside.
Turku
8.7
out of 10
Cautious estimate
Models split — score biased toward the cloudier forecast.
Peak 2h
9.623:00–01:00
Prime 21–01
9.621:00–01:00
Best this week
8.8Sun, Jul 19
Moon
Waxing Crescent
11% lit
Moon doesn’t interfere — perfect darkness
🔭 Moon up: 09:00–23:22
Full moon: Jul 29
Sky now
Clear · 0%
Measured at EFTU · 7km away · 22min ago
Sun ↓ 22:39·Dark from 23:39·70% clouds
Alert me on good nightsSky quality tonight
Best: 23:00–01:00This week’s nights
Europe/HelsinkiHow 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.