{"assessment":{"best_window":{"end":"2027-01-08T04:10Z","end_local":"06:10","hours":11.33,"label":"good","mean_quality":1.0,"start":"2027-01-07T16:50Z","start_local":"18:50"},"cost":{"altitude":0.0,"clouds":0.0,"darkness":2.66,"moon":0.0},"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":"2027-01-07T16:00Z","label":"poor","low":null,"mid":null,"moon_alt":-14,"precip":null,"q":0.15,"rh":null,"sky":"nautical twilight","temp":null,"time":"18:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-07T17:00Z","label":"good","low":null,"mid":null,"moon_alt":-24,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"19:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-07T18:00Z","label":"good","low":null,"mid":null,"moon_alt":-35,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"20:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-07T19:00Z","label":"good","low":null,"mid":null,"moon_alt":-45,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"21:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-07T20:00Z","label":"good","low":null,"mid":null,"moon_alt":-56,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"22:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-07T21:00Z","label":"good","low":null,"mid":null,"moon_alt":-65,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"23:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-07T22:00Z","label":"good","low":null,"mid":null,"moon_alt":-72,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"00:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-07T23:00Z","label":"good","low":null,"mid":null,"moon_alt":-73,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"01:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-08T00:00Z","label":"good","low":null,"mid":null,"moon_alt":-66,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"02:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-08T01:00Z","label":"good","low":null,"mid":null,"moon_alt":-57,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"03:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-08T02:00Z","label":"good","low":null,"mid":null,"moon_alt":-46,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"04:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-08T03:00Z","label":"good","low":null,"mid":null,"moon_alt":-35,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"05:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-08T04:00Z","label":"good","low":null,"mid":null,"moon_alt":-25,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"06:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2027-01-08T05:00Z","label":"poor","low":null,"mid":null,"moon_alt":-14,"precip":null,"q":0.15,"rh":null,"sky":"nautical twilight","temp":null,"time":"07:00","wind":null}],"peak_quality":1.0,"peak_sky":1.0,"quality_hours":12.09,"reasons":["daylight and twilight cost 2.7 quality-hours"],"reference_hours":4.0,"score":null,"score_astronomy":100,"score_weather":null,"sky_hours":12.09,"verdict":"unknown","verdict_astronomy":"good","weather_known":false,"windows":[{"end":"2027-01-07T15:40Z","end_local":"17:40","hours":0.58,"label":"unusable","mean_quality":0.0,"start":"2027-01-07T15:05Z","start_local":"17:05"},{"end":"2027-01-07T16:15Z","end_local":"18:15","hours":0.58,"label":"poor","mean_quality":0.15,"start":"2027-01-07T15:40Z","start_local":"17:40"},{"end":"2027-01-07T16:50Z","end_local":"18:50","hours":0.58,"label":"marginal","mean_quality":0.5,"start":"2027-01-07T16:15Z","start_local":"18:15"},{"end":"2027-01-08T04:10Z","end_local":"06:10","hours":11.33,"label":"good","mean_quality":1.0,"start":"2027-01-07T16:50Z","start_local":"18:50"},{"end":"2027-01-08T04:45Z","end_local":"06:45","hours":0.58,"label":"marginal","mean_quality":0.5,"start":"2027-01-08T04:10Z","start_local":"06:10"},{"end":"2027-01-08T05:20Z","end_local":"07:20","hours":0.58,"label":"poor","mean_quality":0.15,"start":"2027-01-08T04:45Z","start_local":"06:45"},{"end":"2027-01-08T05:50Z","end_local":"07:50","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2027-01-08T05:20Z","start_local":"07:20"}]},"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":"2027-01-07T16:45:59Z","dark_hours":11.38,"dark_to":"2027-01-08T04:08:37Z","moon":{"illumination":0.001,"phase":"new moon","waxing":true},"moon_free_dark_hours":11.37,"moonrise":"2027-01-08T06:29:14Z","moonset":"2027-01-07T14:28:19Z","sunrise":"2027-01-08T05:47:56Z","sunset":"2027-01-07T15:06:31Z","twilight":{"astronomical":{"end":"2027-01-07T16:45:59Z","start":"2027-01-08T04:08:37Z"},"civil":{"end":"2027-01-07T15:37:40Z","start":"2027-01-08T05:16:50Z"},"nautical":{"end":"2027-01-07T16:12:23Z","start":"2027-01-08T04:42:11Z"}},"window_end":"2027-01-08T10:00:00Z","window_start":"2027-01-07T10:00:00Z"},"night_date":"2027-01-07","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."]}