How does Stella decide whether tonight is good for stargazing?

The planner combines moon illumination, the amount of true darkness, and the nearest known dark-sky site's Bortle class into a 0-100 score for the selected coordinates.

Can I share a tonight plan for a specific location?

Yes. Pick a city, preset, or current location, then copy the share link. The URL keeps latitude, longitude, and the display label.

Does the web planner include clouds?

This web version focuses on moonlight, darkness, and nearby dark-sky quality. The Stella app adds live cloud, seeing, transparency, and alerting.

Tonight planner

Is tonight good for stargazing near you?

Search a city, use your location, or open a shared coordinate link. Stella scores tonight with moonlight, true darkness, and the nearest known dark-sky site.

City or observing location

Tonight scoreCalculating...

Cherry Springs, PA

-out of 100

Best moon-free windowMoon up most of the night

Moonlight-

Moon-free dark-

Darkness-

Nearest dark site-

MoonScores the real moonlight penalty

A bright Moon can erase faint meteors and the Milky Way even from dark sites.

DarknessFinds the best moon-free window

The window is computed for the selected coordinates, not a generic city clock.

BortleChecks the nearest known dark site

The score improves when a darker cataloged site is realistically nearby.

Next steps

Turn tonight into a fuller field plan.

Pair the score with dark places, the sky almanac, and practical observing guides.

Dark-sky mapFind a darker nearby site

Browse protected places, observatories, reserves, and parks by darkness and region.

Open routeSky almanacPlan the next dark window

Use Moon phases, meteor peaks, and eclipse timing when tonight is not the night.

Open routeCity guidesCompare nearby stargazing routes

Open long-tail city guides for dark sites, stays, and drive estimates.

Open routeBeginner guideKnow what to look for

Start with bright planets, constellations, and the best targets for your conditions.

Open route

Is tonight good for stargazing near you?

Turn tonight into a fuller field plan.

Stay in the loop