{"assessment":{"best_window":{"end":"2027-07-22T20:40Z","end_local":"23:40","hours":0.83,"label":"good","mean_quality":0.62,"start":"2027-07-22T19:50Z","start_local":"22:50"},"cost":{"altitude":0.0,"clouds":0.0,"darkness":3.13,"moon":2.91},"formula":"astronomy = 100 * min(1, sky_hours / reference_hours) * peak_sky; overall = astronomy * score_weather / 100 (null when the weather is unknown)","hard_limit":null,"headline":"Astronomically possible, with compromises \u2014 weather unknown","hourly":[{"alt":null,"cloud":null,"high":null,"iso":"2027-07-22T18:00Z","label":"unusable","low":null,"mid":null,"moon_alt":-18,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"21:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-22T19:00Z","label":"poor","low":null,"mid":null,"moon_alt":-7,"precip":null,"q":0.15,"rh":null,"sky":"nautical twilight","temp":null,"time":"22:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-22T20:00Z","label":"good","low":null,"mid":null,"moon_alt":4,"precip":null,"q":0.64,"rh":null,"sky":"night","temp":null,"time":"23:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-22T21:00Z","label":"marginal","low":null,"mid":null,"moon_alt":15,"precip":null,"q":0.58,"rh":null,"sky":"night","temp":null,"time":"00:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-22T22:00Z","label":"marginal","low":null,"mid":null,"moon_alt":25,"precip":null,"q":0.52,"rh":null,"sky":"night","temp":null,"time":"01:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-22T23:00Z","label":"marginal","low":null,"mid":null,"moon_alt":34,"precip":null,"q":0.47,"rh":null,"sky":"night","temp":null,"time":"02:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-23T00:00Z","label":"marginal","low":null,"mid":null,"moon_alt":41,"precip":null,"q":0.44,"rh":null,"sky":"night","temp":null,"time":"03:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-23T01:00Z","label":"marginal","low":null,"mid":null,"moon_alt":45,"precip":null,"q":0.42,"rh":null,"sky":"night","temp":null,"time":"04:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-23T02:00Z","label":"poor","low":null,"mid":null,"moon_alt":45,"precip":null,"q":0.06,"rh":null,"sky":"nautical twilight","temp":null,"time":"05:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-23T03:00Z","label":"unusable","low":null,"mid":null,"moon_alt":42,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"06:00","wind":null}],"peak_quality":0.65,"peak_sky":0.65,"quality_hours":3.37,"reasons":["daylight and twilight cost 3.1 quality-hours","moonlight cost 2.9 quality-hours"],"reference_hours":4.0,"score":null,"score_astronomy":55,"score_weather":null,"sky_hours":3.37,"verdict":"unknown","verdict_astronomy":"marginal","weather_known":false,"windows":[{"end":"2027-07-22T18:25Z","end_local":"21:25","hours":0.67,"label":"unusable","mean_quality":0.0,"start":"2027-07-22T17:45Z","start_local":"20:45"},{"end":"2027-07-22T19:05Z","end_local":"22:05","hours":0.67,"label":"poor","mean_quality":0.15,"start":"2027-07-22T18:25Z","start_local":"21:25"},{"end":"2027-07-22T19:50Z","end_local":"22:50","hours":0.75,"label":"marginal","mean_quality":0.46,"start":"2027-07-22T19:05Z","start_local":"22:05"},{"end":"2027-07-22T20:40Z","end_local":"23:40","hours":0.83,"label":"good","mean_quality":0.62,"start":"2027-07-22T19:50Z","start_local":"22:50"},{"end":"2027-07-23T01:10Z","end_local":"04:10","hours":4.5,"label":"marginal","mean_quality":0.49,"start":"2027-07-22T20:40Z","start_local":"23:40"},{"end":"2027-07-23T02:35Z","end_local":"05:35","hours":1.42,"label":"poor","mean_quality":0.14,"start":"2027-07-23T01:10Z","start_local":"04:10"},{"end":"2027-07-23T03:10Z","end_local":"06:10","hours":0.58,"label":"unusable","mean_quality":0.0,"start":"2027-07-23T02:35Z","start_local":"05:35"}]},"calculation_version":"2026-10-10.1","forecast":[],"forecast_source":"none","forecast_updated_at":null,"limits":{"good_alt":30.0,"usable_alt":20.0},"night":{"dark_from":"2027-07-22T19:48:27Z","dark_hours":5.31,"dark_to":"2027-07-23T01:07:00Z","moon":{"illumination":0.843,"phase":"waning gibbous","waxing":false},"moon_free_dark_hours":0.0,"moonrise":"2027-07-22T19:37:18Z","moonset":"2027-07-23T07:32:17Z","sunrise":"2027-07-23T03:06:17Z","sunset":"2027-07-22T17:49:10Z","twilight":{"astronomical":{"end":"2027-07-22T19:48:27Z","start":"2027-07-23T01:07:00Z"},"civil":{"end":"2027-07-22T18:21:30Z","start":"2027-07-23T02:33:57Z"},"nautical":{"end":"2027-07-22T19:02:06Z","start":"2027-07-23T01:53:21Z"}},"window_end":"2027-07-23T09:00:00Z","window_start":"2027-07-22T09:00:00Z"},"night_date":"2027-07-22","site":{"elev_m":1750,"lat":41.693,"lon":24.739,"name":"NAO Rozhen"},"warnings":["No cloud data for this night (beyond the 4-day forecast, or not yet in the archive) \u2014 the score is geometry only."]}
