StarsOut
Should you go outside tonight?
Drop everything — go outside
Near-perfect conditions. Nights like this are rare.
Sapporo
9.2
out of 10
Peak 2h
9.900:00–02:00
Prime 21–01
9.621:00–01:00
Best this week
8.5Tue, Jul 21
Moon
Waxing Crescent
5% lit
Moon doesn’t interfere — perfect darkness
🔭 Moon up: 05:56–20:33
📍 W · 27°
Full moon: Jul 29
Sun ↓ 19:11·Dark from 20:11·33% clouds
Alert me on good nightsSky quality tonight
Best: 00:00–02:00This week’s nights
Asia/TokyoHow 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.