{"assessment":{"best_window":{"end":"2027-07-09T00:50Z","end_local":"03:50","hours":4.75,"label":"good","mean_quality":0.99,"start":"2027-07-08T20:05Z","start_local":"23:05"},"cost":{"altitude":0.0,"clouds":0.0,"darkness":3.2,"moon":0.14},"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 worth it \u2014 weather unknown","hourly":[{"alt":null,"cloud":null,"high":null,"iso":"2027-07-08T18:00Z","label":"unusable","low":null,"mid":null,"moon_alt":28,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"21:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-08T19:00Z","label":"poor","low":null,"mid":null,"moon_alt":17,"precip":null,"q":0.13,"rh":null,"sky":"nautical twilight","temp":null,"time":"22:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-08T20:00Z","label":"marginal","low":null,"mid":null,"moon_alt":6,"precip":null,"q":0.43,"rh":null,"sky":"astronomical twilight","temp":null,"time":"23:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-08T21:00Z","label":"good","low":null,"mid":null,"moon_alt":-5,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"00:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-08T22:00Z","label":"good","low":null,"mid":null,"moon_alt":-15,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"01:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-08T23:00Z","label":"good","low":null,"mid":null,"moon_alt":-26,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"02:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-09T00:00Z","label":"good","low":null,"mid":null,"moon_alt":-35,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"03:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-09T01:00Z","label":"marginal","low":null,"mid":null,"moon_alt":-43,"precip":null,"q":0.5,"rh":null,"sky":"astronomical twilight","temp":null,"time":"04:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-07-09T02:00Z","label":"poor","low":null,"mid":null,"moon_alt":-49,"precip":null,"q":0.15,"rh":null,"sky":"nautical twilight","temp":null,"time":"05:00","wind":null}],"peak_quality":1.0,"peak_sky":1.0,"quality_hours":5.66,"reasons":["daylight and twilight cost 3.2 quality-hours"],"reference_hours":4.0,"score":null,"score_astronomy":100,"score_weather":null,"sky_hours":5.66,"verdict":"unknown","verdict_astronomy":"good","weather_known":false,"windows":[{"end":"2027-07-08T18:35Z","end_local":"21:35","hours":0.67,"label":"unusable","mean_quality":0.0,"start":"2027-07-08T17:55Z","start_local":"20:55"},{"end":"2027-07-08T19:15Z","end_local":"22:15","hours":0.67,"label":"poor","mean_quality":0.13,"start":"2027-07-08T18:35Z","start_local":"21:35"},{"end":"2027-07-08T20:05Z","end_local":"23:05","hours":0.83,"label":"marginal","mean_quality":0.43,"start":"2027-07-08T19:15Z","start_local":"22:15"},{"end":"2027-07-09T00:50Z","end_local":"03:50","hours":4.75,"label":"good","mean_quality":0.99,"start":"2027-07-08T20:05Z","start_local":"23:05"},{"end":"2027-07-09T01:40Z","end_local":"04:40","hours":0.83,"label":"marginal","mean_quality":0.5,"start":"2027-07-09T00:50Z","start_local":"03:50"},{"end":"2027-07-09T02:25Z","end_local":"05:25","hours":0.75,"label":"poor","mean_quality":0.15,"start":"2027-07-09T01:40Z","start_local":"04:40"},{"end":"2027-07-09T02:55Z","end_local":"05:55","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2027-07-09T02:25Z","start_local":"05:25"}]},"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":"2027-07-08T20:04:39Z","dark_hours":4.72,"dark_to":"2027-07-09T00:47:58Z","moon":{"illumination":0.301,"phase":"waxing crescent","waxing":true},"moon_free_dark_hours":4.2,"moonrise":null,"moonset":"2027-07-08T20:34:13Z","sunrise":"2027-07-09T02:54:54Z","sunset":"2027-07-08T17:57:43Z","twilight":{"astronomical":{"end":"2027-07-08T20:04:39Z","start":"2027-07-09T00:47:58Z"},"civil":{"end":"2027-07-08T18:31:17Z","start":"2027-07-09T02:21:20Z"},"nautical":{"end":"2027-07-08T19:14:07Z","start":"2027-07-09T01:38:30Z"}},"window_end":"2027-07-09T09:00:00Z","window_start":"2027-07-08T09:00:00Z"},"night_date":"2027-07-08","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."]}