{"assessment":{"best_window":{"end":"2027-09-28T02:45Z","end_local":"05:45","hours":9.0,"label":"good","mean_quality":1.0,"start":"2027-09-27T17:45Z","start_local":"20:45"},"cost":{"altitude":0.0,"clouds":0.0,"darkness":2.41,"moon":0.03},"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":"2027-09-27T17:00Z","label":"poor","low":null,"mid":null,"moon_alt":-24,"precip":null,"q":0.15,"rh":null,"sky":"nautical twilight","temp":null,"time":"20:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-27T18:00Z","label":"good","low":null,"mid":null,"moon_alt":-32,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"21:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-27T19:00Z","label":"good","low":null,"mid":null,"moon_alt":-38,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"22:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-27T20:00Z","label":"good","low":null,"mid":null,"moon_alt":-41,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"23:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-27T21:00Z","label":"good","low":null,"mid":null,"moon_alt":-40,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"00:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-27T22:00Z","label":"good","low":null,"mid":null,"moon_alt":-36,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"01:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-27T23:00Z","label":"good","low":null,"mid":null,"moon_alt":-29,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"02:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-28T00:00Z","label":"good","low":null,"mid":null,"moon_alt":-21,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"03:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-28T01:00Z","label":"good","low":null,"mid":null,"moon_alt":-12,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"04:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-28T02:00Z","label":"good","low":null,"mid":null,"moon_alt":-1,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"05:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-28T03:00Z","label":"marginal","low":null,"mid":null,"moon_alt":9,"precip":null,"q":0.48,"rh":null,"sky":"astronomical twilight","temp":null,"time":"06:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-09-28T04:00Z","label":"unusable","low":null,"mid":null,"moon_alt":20,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"07:00","wind":null}],"peak_quality":1.0,"peak_sky":1.0,"quality_hours":9.65,"reasons":["daylight and twilight cost 2.4 quality-hours"],"reference_hours":4.0,"score":null,"score_astronomy":100,"score_weather":null,"sky_hours":9.65,"verdict":"unknown","verdict_astronomy":"good","weather_known":false,"windows":[{"end":"2027-09-27T16:40Z","end_local":"19:40","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2027-09-27T16:10Z","start_local":"19:10"},{"end":"2027-09-27T17:15Z","end_local":"20:15","hours":0.58,"label":"poor","mean_quality":0.15,"start":"2027-09-27T16:40Z","start_local":"19:40"},{"end":"2027-09-27T17:45Z","end_local":"20:45","hours":0.5,"label":"marginal","mean_quality":0.5,"start":"2027-09-27T17:15Z","start_local":"20:15"},{"end":"2027-09-28T02:45Z","end_local":"05:45","hours":9.0,"label":"good","mean_quality":1.0,"start":"2027-09-27T17:45Z","start_local":"20:45"},{"end":"2027-09-28T03:15Z","end_local":"06:15","hours":0.5,"label":"marginal","mean_quality":0.48,"start":"2027-09-28T02:45Z","start_local":"05:45"},{"end":"2027-09-28T03:50Z","end_local":"06:50","hours":0.58,"label":"poor","mean_quality":0.14,"start":"2027-09-28T03:15Z","start_local":"06:15"},{"end":"2027-09-28T04:15Z","end_local":"07:15","hours":0.42,"label":"unusable","mean_quality":0.0,"start":"2027-09-28T03:50Z","start_local":"06:50"}]},"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":"2027-09-27T17:43:04Z","dark_hours":8.97,"dark_to":"2027-09-28T02:41:26Z","moon":{"illumination":0.067,"phase":"waning crescent","waxing":false},"moon_free_dark_hours":8.4,"moonrise":"2027-09-28T02:08:01Z","moonset":"2027-09-27T14:32:01Z","sunrise":"2027-09-28T04:14:15Z","sunset":"2027-09-27T16:10:22Z","twilight":{"astronomical":{"end":"2027-09-27T17:43:04Z","start":"2027-09-28T02:41:26Z"},"civil":{"end":"2027-09-27T16:38:02Z","start":"2027-09-28T03:46:33Z"},"nautical":{"end":"2027-09-27T17:10:18Z","start":"2027-09-28T03:14:13Z"}},"window_end":"2027-09-28T09:00:00Z","window_start":"2027-09-27T09:00:00Z"},"night_date":"2027-09-27","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."]}
