{"calculation_version":"2026-10-10.1","days":30,"nights":[{"best_hours":2.75,"best_label":"good","best_window":"01:50\u201304:35","dark_hours":6.47,"date":"2025-04-29","moon_free_dark_hours":5.68,"moon_illumination":7,"moon_separation":108.9,"score":73,"score_astronomy":73,"score_weather":100,"transit_alt":71.1,"transit_local":"06:50","verdict":"good","weather_source":"history","weekday":"Tue"},{"best_hours":2.5,"best_label":"good","best_window":"02:05\u201304:35","dark_hours":6.41,"date":"2025-04-30","moon_free_dark_hours":4.42,"moon_illumination":14,"moon_separation":117.9,"score":65,"score_astronomy":75,"score_weather":87,"transit_alt":71.1,"transit_local":"06:45","verdict":"marginal","weather_source":"history","weekday":"Wed"},{"best_hours":1.5,"best_label":"marginal","best_window":"03:00\u201304:30","dark_hours":6.35,"date":"2025-05-01","moon_free_dark_hours":3.35,"moon_illumination":23,"moon_separation":125.5,"score":23,"score_astronomy":75,"score_weather":30,"transit_alt":71.1,"transit_local":"06:40","verdict":"poor","weather_source":"history","weekday":"Thu"},{"best_hours":2.83,"best_label":"good","best_window":"01:40\u201304:30","dark_hours":6.29,"date":"2025-05-02","moon_free_dark_hours":2.5,"moon_illumination":33,"moon_separation":130.9,"score":76,"score_astronomy":76,"score_weather":99,"transit_alt":71.1,"transit_local":"06:40","verdict":"good","weather_source":"history","weekday":"Fri"},{"best_hours":2.83,"best_label":"good","best_window":"01:35\u201304:25","dark_hours":6.23,"date":"2025-05-03","moon_free_dark_hours":1.85,"moon_illumination":43,"moon_separation":133.8,"score":76,"score_astronomy":76,"score_weather":100,"transit_alt":71.1,"transit_local":"06:35","verdict":"good","weather_source":"history","weekday":"Sat"},{"best_hours":0.08,"best_label":"marginal","best_window":"05:00\u201305:05","dark_hours":6.18,"date":"2025-05-04","moon_free_dark_hours":1.33,"moon_illumination":54,"moon_separation":133.8,"score":7,"score_astronomy":77,"score_weather":9,"transit_alt":71.1,"transit_local":"06:30","verdict":"poor","weather_source":"history","weekday":"Sun"},{"best_hours":0.42,"best_label":"good","best_window":"04:00\u201304:25","dark_hours":6.12,"date":"2025-05-05","moon_free_dark_hours":0.92,"moon_illumination":64,"moon_separation":131.2,"score":58,"score_astronomy":78,"score_weather":74,"transit_alt":71.1,"transit_local":"06:25","verdict":"marginal","weather_source":"history","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.06,"date":"2025-05-06","moon_free_dark_hours":0.55,"moon_illumination":73,"moon_separation":126.5,"score":0,"score_astronomy":76,"score_weather":0,"transit_alt":71.1,"transit_local":"06:20","verdict":"unusable","weather_source":"history","weekday":"Tue"},{"best_hours":2.5,"best_label":"good","best_window":"01:30\u201304:00","dark_hours":6.0,"date":"2025-05-07","moon_free_dark_hours":0.22,"moon_illumination":81,"moon_separation":120.4,"score":54,"score_astronomy":76,"score_weather":71,"transit_alt":71.1,"transit_local":"06:20","verdict":"marginal","weather_source":"history","weekday":"Wed"},{"best_hours":2.58,"best_label":"good","best_window":"01:25\u201304:00","dark_hours":5.95,"date":"2025-05-08","moon_free_dark_hours":0.0,"moon_illumination":88,"moon_separation":113.3,"score":49,"score_astronomy":68,"score_weather":72,"transit_alt":71.1,"transit_local":"06:15","verdict":"marginal","weather_source":"history","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.89,"date":"2025-05-09","moon_free_dark_hours":0.0,"moon_illumination":93,"moon_separation":105.6,"score":0,"score_astronomy":62,"score_weather":0,"transit_alt":71.1,"transit_local":"06:10","verdict":"unusable","weather_source":"history","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.84,"date":"2025-05-10","moon_free_dark_hours":0.0,"moon_illumination":97,"moon_separation":97.6,"score":0,"score_astronomy":56,"score_weather":0,"transit_alt":71.1,"transit_local":"06:05","verdict":"unusable","weather_source":"history","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.78,"date":"2025-05-11","moon_free_dark_hours":0.0,"moon_illumination":99,"moon_separation":89.4,"score":0,"score_astronomy":51,"score_weather":0,"transit_alt":71.1,"transit_local":"06:00","verdict":"unusable","weather_source":"history","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.73,"date":"2025-05-12","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":81.1,"score":0,"score_astronomy":45,"score_weather":0,"transit_alt":71.1,"transit_local":"06:00","verdict":"unusable","weather_source":"history","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.67,"date":"2025-05-13","moon_free_dark_hours":0.0,"moon_illumination":98,"moon_separation":73.1,"score":0,"score_astronomy":42,"score_weather":0,"transit_alt":71.1,"transit_local":"05:55","verdict":"unusable","weather_source":"history","weekday":"Tue"},{"best_hours":1.25,"best_label":"good","best_window":"02:55\u201304:10","dark_hours":5.62,"date":"2025-05-14","moon_free_dark_hours":0.42,"moon_illumination":95,"moon_separation":65.3,"score":40,"score_astronomy":40,"score_weather":100,"transit_alt":71.1,"transit_local":"05:50","verdict":"marginal","weather_source":"history","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.56,"date":"2025-05-15","moon_free_dark_hours":1.32,"moon_illumination":90,"moon_separation":58.3,"score":0,"score_astronomy":38,"score_weather":0,"transit_alt":71.1,"transit_local":"05:45","verdict":"unusable","weather_source":"history","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.51,"date":"2025-05-16","moon_free_dark_hours":2.12,"moon_illumination":84,"moon_separation":52.3,"score":0,"score_astronomy":41,"score_weather":0,"transit_alt":71.1,"transit_local":"05:45","verdict":"unusable","weather_source":"history","weekday":"Fri"},{"best_hours":0.75,"best_label":"marginal","best_window":"00:15\u201301:00","dark_hours":5.46,"date":"2025-05-17","moon_free_dark_hours":2.77,"moon_illumination":76,"moon_separation":47.9,"score":9,"score_astronomy":58,"score_weather":16,"transit_alt":71.1,"transit_local":"05:40","verdict":"poor","weather_source":"history","weekday":"Sat"},{"best_hours":3.42,"best_label":"good","best_window":"00:35\u201304:00","dark_hours":5.41,"date":"2025-05-18","moon_free_dark_hours":3.28,"moon_illumination":66,"moon_separation":45.9,"score":67,"score_astronomy":67,"score_weather":100,"transit_alt":71.1,"transit_local":"05:35","verdict":"marginal","weather_source":"history","weekday":"Sun"},{"best_hours":3.33,"best_label":"good","best_window":"00:40\u201304:00","dark_hours":5.36,"date":"2025-05-19","moon_free_dark_hours":3.73,"moon_illumination":56,"moon_separation":46.6,"score":73,"score_astronomy":76,"score_weather":96,"transit_alt":71.1,"transit_local":"05:30","verdict":"good","weather_source":"history","weekday":"Mon"},{"best_hours":1.0,"best_label":"good","best_window":"03:00\u201304:00","dark_hours":5.31,"date":"2025-05-20","moon_free_dark_hours":4.1,"moon_illumination":45,"moon_separation":50.1,"score":24,"score_astronomy":83,"score_weather":28,"transit_alt":71.1,"transit_local":"05:25","verdict":"poor","weather_source":"history","weekday":"Tue"},{"best_hours":1.5,"best_label":"good","best_window":"00:30\u201302:00","dark_hours":5.26,"date":"2025-05-21","moon_free_dark_hours":4.45,"moon_illumination":34,"moon_separation":56.2,"score":68,"score_astronomy":92,"score_weather":73,"transit_alt":71.1,"transit_local":"05:25","verdict":"marginal","weather_source":"history","weekday":"Wed"},{"best_hours":3.58,"best_label":"good","best_window":"00:20\u201303:55","dark_hours":5.21,"date":"2025-05-22","moon_free_dark_hours":4.78,"moon_illumination":24,"moon_separation":64.1,"score":93,"score_astronomy":97,"score_weather":96,"transit_alt":71.1,"transit_local":"05:20","verdict":"good","weather_source":"history","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.16,"date":"2025-05-23","moon_free_dark_hours":5.15,"moon_illumination":15,"moon_separation":73.4,"score":5,"score_astronomy":100,"score_weather":5,"transit_alt":71.1,"transit_local":"05:15","verdict":"poor","weather_source":"history","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.12,"date":"2025-05-24","moon_free_dark_hours":5.1,"moon_illumination":7,"moon_separation":83.6,"score":0,"score_astronomy":100,"score_weather":0,"transit_alt":71.1,"transit_local":"05:10","verdict":"unusable","weather_source":"history","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.07,"date":"2025-05-25","moon_free_dark_hours":5.07,"moon_illumination":2,"moon_separation":94.1,"score":0,"score_astronomy":100,"score_weather":0,"transit_alt":71.1,"transit_local":"05:05","verdict":"unusable","weather_source":"history","weekday":"Sun"},{"best_hours":2.42,"best_label":"good","best_window":"01:25\u201303:50","dark_hours":5.03,"date":"2025-05-26","moon_free_dark_hours":5.0,"moon_illumination":0,"moon_separation":104.5,"score":75,"score_astronomy":100,"score_weather":75,"transit_alt":71.1,"transit_local":"05:05","verdict":"good","weather_source":"history","weekday":"Mon"},{"best_hours":3.83,"best_label":"good","best_window":"00:00\u201303:50","dark_hours":4.98,"date":"2025-05-27","moon_free_dark_hours":4.97,"moon_illumination":1,"moon_separation":114.2,"score":99,"score_astronomy":100,"score_weather":99,"transit_alt":71.1,"transit_local":"05:00","verdict":"good","weather_source":"history","weekday":"Tue"},{"best_hours":3.92,"best_label":"good","best_window":"23:55\u201303:50","dark_hours":4.94,"date":"2025-05-28","moon_free_dark_hours":4.92,"moon_illumination":5,"moon_separation":122.7,"score":91,"score_astronomy":100,"score_weather":91,"transit_alt":71.1,"transit_local":"04:55","verdict":"good","weather_source":"history","weekday":"Wed"}],"note":"score_astronomy for every night; score_weather/score only where a forecast (next 4 days) or ERA5 history exists \u2014 null otherwise","start":"2025-04-29","target":{"dec":22.71085365,"name":"HD 189733","ra":300.18213726,"simbad_url":"https://simbad.cds.unistra.fr/simbad/sim-id?Ident=HD%20189733","source":"sesame","spectral_type":"K2V","type":"BY*","type_text":"BY Draconis variable \u2014 a spotted, rotating star","vmag":7.648}}
