Likelihood of visible crescent new moon
Pick the city nearest you and a new moon, then nudge the sky conditions to see your chances of spotting the crescent on each of the first three evenings.
Quick select:
Atmospheric Conditions
0% clear → 100% overcast
Results for the three evenings after conjunction
Location context
Map shown for geographic context only (marker at the selected city).
How to read the visibility rating
A Easily visible to the naked eye
B Visible naked eye under good conditions
C Visible naked eye, but requires effort
B Visible naked eye under good conditions
C Visible naked eye, but requires effort
D Usually needs binoculars or a telescope
E Very difficult or not visible even with aid
E Very difficult or not visible even with aid
Raw: pure astronomical prediction using the Yallop criterion at the city's location and time.
Effective: adjusted for the cloud cover and transparency you entered.
Age: hours since the exact moment of new moon (conjunction).
Q: model quality factor (higher generally indicates more favorable geometry).
Yallop criterion (clear-sky baseline). Atmospheric adjustment applied live in the browser using the same model as the reference web app. No astronomy is computed at runtime. Plugin v0.3.12