{"assessment":{"best_window":{"end":"2026-12-01T03:50Z","end_local":"05:50","hours":11.25,"label":"good","mean_quality":0.82,"start":"2026-11-30T16:35Z","start_local":"18:35"},"cost":{"altitude":0.0,"clouds":0.0,"darkness":2.66,"moon":2.12},"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":"2026-11-30T15:00Z","label":"unusable","low":null,"mid":null,"moon_alt":-37,"precip":null,"q":0.0,"rh":null,"sky":"civil twilight","temp":null,"time":"17:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-30T16:00Z","label":"marginal","low":null,"mid":null,"moon_alt":-39,"precip":null,"q":0.5,"rh":null,"sky":"astronomical twilight","temp":null,"time":"18:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-30T17:00Z","label":"good","low":null,"mid":null,"moon_alt":-37,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"19:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-30T18:00Z","label":"good","low":null,"mid":null,"moon_alt":-32,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"20:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-30T19:00Z","label":"good","low":null,"mid":null,"moon_alt":-25,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"21:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-30T20:00Z","label":"good","low":null,"mid":null,"moon_alt":-16,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"22:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-30T21:00Z","label":"good","low":null,"mid":null,"moon_alt":-6,"precip":null,"q":1.0,"rh":null,"sky":"night","temp":null,"time":"23:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-30T22:00Z","label":"good","low":null,"mid":null,"moon_alt":4,"precip":null,"q":0.77,"rh":null,"sky":"night","temp":null,"time":"00:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-11-30T23:00Z","label":"good","low":null,"mid":null,"moon_alt":15,"precip":null,"q":0.73,"rh":null,"sky":"night","temp":null,"time":"01:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-12-01T00:00Z","label":"good","low":null,"mid":null,"moon_alt":25,"precip":null,"q":0.69,"rh":null,"sky":"night","temp":null,"time":"02:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-12-01T01:00Z","label":"good","low":null,"mid":null,"moon_alt":35,"precip":null,"q":0.66,"rh":null,"sky":"night","temp":null,"time":"03:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-12-01T02:00Z","label":"good","low":null,"mid":null,"moon_alt":45,"precip":null,"q":0.64,"rh":null,"sky":"night","temp":null,"time":"04:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-12-01T03:00Z","label":"good","low":null,"mid":null,"moon_alt":52,"precip":null,"q":0.62,"rh":null,"sky":"night","temp":null,"time":"05:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-12-01T04:00Z","label":"marginal","low":null,"mid":null,"moon_alt":55,"precip":null,"q":0.3,"rh":null,"sky":"astronomical twilight","temp":null,"time":"06:00","wind":null},{"alt":null,"cloud":null,"high":null,"iso":"2026-12-01T05:00Z","label":"unusable","low":null,"mid":null,"moon_alt":54,"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":9.89,"reasons":["daylight and twilight cost 2.7 quality-hours","moonlight cost 2.1 quality-hours"],"reference_hours":4.0,"score":null,"score_astronomy":100,"score_weather":null,"sky_hours":9.89,"verdict":"unknown","verdict_astronomy":"good","weather_known":false,"windows":[{"end":"2026-11-30T15:25Z","end_local":"17:25","hours":0.58,"label":"unusable","mean_quality":0.0,"start":"2026-11-30T14:50Z","start_local":"16:50"},{"end":"2026-11-30T16:00Z","end_local":"18:00","hours":0.58,"label":"poor","mean_quality":0.15,"start":"2026-11-30T15:25Z","start_local":"17:25"},{"end":"2026-11-30T16:35Z","end_local":"18:35","hours":0.58,"label":"marginal","mean_quality":0.5,"start":"2026-11-30T16:00Z","start_local":"18:00"},{"end":"2026-12-01T03:50Z","end_local":"05:50","hours":11.25,"label":"good","mean_quality":0.82,"start":"2026-11-30T16:35Z","start_local":"18:35"},{"end":"2026-12-01T04:25Z","end_local":"06:25","hours":0.58,"label":"marginal","mean_quality":0.3,"start":"2026-12-01T03:50Z","start_local":"05:50"},{"end":"2026-12-01T05:00Z","end_local":"07:00","hours":0.58,"label":"poor","mean_quality":0.09,"start":"2026-12-01T04:25Z","start_local":"06:25"},{"end":"2026-12-01T05:30Z","end_local":"07:30","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2026-12-01T05:00Z","start_local":"07:00"}]},"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":"2026-11-30T16:30:34Z","dark_hours":11.31,"dark_to":"2026-12-01T03:49:23Z","moon":{"illumination":0.536,"phase":"waning gibbous","waxing":false},"moon_free_dark_hours":5.12,"moonrise":"2026-11-30T21:38:11Z","moonset":"2026-11-30T10:20:36Z","sunrise":"2026-12-01T05:28:20Z","sunset":"2026-11-30T14:51:47Z","twilight":{"astronomical":{"end":"2026-11-30T16:30:34Z","start":"2026-12-01T03:49:23Z"},"civil":{"end":"2026-11-30T15:22:40Z","start":"2026-12-01T04:57:23Z"},"nautical":{"end":"2026-11-30T15:57:08Z","start":"2026-12-01T04:22:52Z"}},"window_end":"2026-12-01T10:00:00Z","window_start":"2026-11-30T10:00:00Z"},"night_date":"2026-11-30","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."]}