The Dark-Sky Engine API

Everything on this site — tonight's targets, dark windows, moon timing, clear-sky outlooks — is computed by our Dark-Sky Engine. The same engine is available to partner websites, free, as a JSON API and a drop-in embeddable widget.

Send the engine a place name, latitude/longitude, and a date. It answers with the complete picture for that night at that exact spot: sunset and sunrise, twilight phases and the true-darkness window, moonrise/set with phase and illumination, and a ranked list of the best celestial targets — each with position, all-night motion track, smart-telescope suitability, and NASA imagery. Astronomy is computed from JPL ephemerides and is exact for any date, past or future. A clear-sky forecast (cloud, transparency, seeing) is included when the date is within the weather horizon, and always labeled as a forecast.

The exact component a partner embed renders, running here live. Click a target, step nights, or play the dusk-to-dawn time-lapse.

The widget installs with a single script tag and sizes itself to its container, from full-width layouts down to phones, with no scrollbars:

<script src="https://smartscope.club/embed/v1.js"
        data-park="zion" data-key="YOUR_PARTNER_KEY"></script>

Use data-park with any U.S. national park code, or data-lat / data-lon / data-name for any coordinates you have — campgrounds, trailheads, observing sites. Optional data-date and data-date-end preset a trip range. Prefer raw data? The JSON API (POST /v1/darksky-lookup) returns the full structured response with both machine fields and pre-rendered human-readable summaries.

Partner keys are free and hand-issued. Embeds carry a small "Powered by SmartScopeClub" badge that links back here — that stays visible; it's how the free tier pays for itself. Keys are rate-limited and per-partner usage is logged. That's the whole deal. See our Terms for the fine print.

Tell us where the widget or API will live. We review every application by hand and reply with your key and setup instructions.