StarsOut
Should you go outside tonight?
Drop everything — go outside
Near-perfect conditions. Nights like this are rare.
Calgary
9.9
out of 10
Peak 2h
10.000:00–02:00
Prime 21–01
9.921:00–01:00
Best this week
10.0Sat, Jul 18
Moon
Waxing Crescent
2% lit
Moon doesn’t interfere — perfect darkness
🔭 Moon up: 07:05–22:48
📍 W · 9°
Full moon: Jul 29
Sky now
Partly cloudy · 38%
Measured at CYYC · 9km away · 42min ago
Sun ↓ 21:45·Dark from 22:45·4% clouds
Alert me on good nightsSky quality tonight
Best: 00:00–02:00This week’s nights
America/EdmontonHow 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.