{"assessment":{"best_window":{"end":"2027-02-21T03:40Z","end_local":"05:40","hours":3.17,"label":"marginal","mean_quality":0.38,"start":"2027-02-21T00:30Z","start_local":"02:30"},"cost":{"altitude":0.0,"clouds":0.0,"darkness":2.41,"moon":7.02},"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":"2027-02-20T16:00Z","label":"unusable","low":null,"mid":null,"moon_alt":4,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"18:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-20T17:00Z","label":"poor","low":null,"mid":null,"moon_alt":14,"precip":null,"q":0.08,"rh":null,"sky":"nautical twilight","temp":null,"time":"19:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-20T18:00Z","label":"marginal","low":null,"mid":null,"moon_alt":25,"precip":null,"q":0.43,"rh":null,"sky":"night","temp":null,"time":"20:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-20T19:00Z","label":"marginal","low":null,"mid":null,"moon_alt":35,"precip":null,"q":0.37,"rh":null,"sky":"night","temp":null,"time":"21:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-20T20:00Z","label":"marginal","low":null,"mid":null,"moon_alt":45,"precip":null,"q":0.32,"rh":null,"sky":"night","temp":null,"time":"22:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-20T21:00Z","label":"poor","low":null,"mid":null,"moon_alt":53,"precip":null,"q":0.28,"rh":null,"sky":"night","temp":null,"time":"23:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-20T22:00Z","label":"poor","low":null,"mid":null,"moon_alt":57,"precip":null,"q":0.26,"rh":null,"sky":"night","temp":null,"time":"00:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-20T23:00Z","label":"poor","low":null,"mid":null,"moon_alt":57,"precip":null,"q":0.26,"rh":null,"sky":"night","temp":null,"time":"01:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-21T00:00Z","label":"poor","low":null,"mid":null,"moon_alt":52,"precip":null,"q":0.28,"rh":null,"sky":"night","temp":null,"time":"02:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-21T01:00Z","label":"marginal","low":null,"mid":null,"moon_alt":44,"precip":null,"q":0.32,"rh":null,"sky":"night","temp":null,"time":"03:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-21T02:00Z","label":"marginal","low":null,"mid":null,"moon_alt":34,"precip":null,"q":0.37,"rh":null,"sky":"night","temp":null,"time":"04:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-21T03:00Z","label":"marginal","low":null,"mid":null,"moon_alt":24,"precip":null,"q":0.44,"rh":null,"sky":"night","temp":null,"time":"05:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-21T04:00Z","label":"poor","low":null,"mid":null,"moon_alt":13,"precip":null,"q":0.26,"rh":null,"sky":"astronomical twilight","temp":null,"time":"06:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-02-21T05:00Z","label":"unusable","low":null,"mid":null,"moon_alt":2,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"07:00","wind":null}],"peak_quality":0.48,"peak_sky":0.48,"quality_hours":3.74,"reasons":["moonlight cost 7.0 quality-hours","daylight and twilight cost 2.4 quality-hours"],"reference_hours":4.0,"score":null,"score_astronomy":45,"score_weather":null,"sky_hours":3.74,"verdict":"unknown","verdict_astronomy":"marginal","weather_known":false,"windows":[{"end":"2027-02-20T16:30Z","end_local":"18:30","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2027-02-20T16:00Z","start_local":"18:00"},{"end":"2027-02-20T17:35Z","end_local":"19:35","hours":1.08,"label":"poor","mean_quality":0.15,"start":"2027-02-20T16:30Z","start_local":"18:30"},{"end":"2027-02-20T20:30Z","end_local":"22:30","hours":2.92,"label":"marginal","mean_quality":0.37,"start":"2027-02-20T17:35Z","start_local":"19:35"},{"end":"2027-02-21T00:30Z","end_local":"02:30","hours":4.0,"label":"poor","mean_quality":0.27,"start":"2027-02-20T20:30Z","start_local":"22:30"},{"end":"2027-02-21T03:40Z","end_local":"05:40","hours":3.17,"label":"marginal","mean_quality":0.38,"start":"2027-02-21T00:30Z","start_local":"02:30"},{"end":"2027-02-21T04:45Z","end_local":"06:45","hours":1.08,"label":"poor","mean_quality":0.16,"start":"2027-02-21T03:40Z","start_local":"05:40"},{"end":"2027-02-21T05:10Z","end_local":"07:10","hours":0.42,"label":"unusable","mean_quality":0.0,"start":"2027-02-21T04:45Z","start_local":"06:45"}]},"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":"2027-02-20T17:32:55Z","dark_hours":10.05,"dark_to":"2027-02-21T03:35:59Z","moon":{"illumination":1.0,"phase":"full moon","waxing":true},"moon_free_dark_hours":0.0,"moonrise":"2027-02-20T15:40:07Z","moonset":"2027-02-21T05:08:30Z","sunrise":"2027-02-21T05:08:38Z","sunset":"2027-02-20T16:00:04Z","twilight":{"astronomical":{"end":"2027-02-20T17:32:55Z","start":"2027-02-21T03:35:59Z"},"civil":{"end":"2027-02-20T16:28:21Z","start":"2027-02-21T04:40:26Z"},"nautical":{"end":"2027-02-20T17:00:44Z","start":"2027-02-21T04:08:07Z"}},"window_end":"2027-02-21T10:00:00Z","window_start":"2027-02-20T10:00:00Z"},"night_date":"2027-02-20","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."]}
