{"calculation_version":"2026-10-10.1","days":30,"nights":[{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.5,"date":"2026-06-29","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":142.4,"score":0,"score_astronomy":0,"score_weather":96,"transit_alt":72.5,"transit_local":"10:35","verdict":"unusable","weather_source":"history","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.52,"date":"2026-06-30","moon_free_dark_hours":0.0,"moon_illumination":99,"moon_separation":130.5,"score":0,"score_astronomy":0,"score_weather":80,"transit_alt":72.5,"transit_local":"10:30","verdict":"unusable","weather_source":"history","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.54,"date":"2026-07-01","moon_free_dark_hours":0.0,"moon_illumination":96,"moon_separation":118.4,"score":0,"score_astronomy":0,"score_weather":33,"transit_alt":72.5,"transit_local":"10:30","verdict":"unusable","weather_source":"history","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.56,"date":"2026-07-02","moon_free_dark_hours":0.0,"moon_illumination":92,"moon_separation":106.3,"score":0,"score_astronomy":0,"score_weather":86,"transit_alt":72.5,"transit_local":"10:25","verdict":"unusable","weather_source":"history","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.58,"date":"2026-07-03","moon_free_dark_hours":0.17,"moon_illumination":86,"moon_separation":94.0,"score":0,"score_astronomy":0,"score_weather":61,"transit_alt":72.5,"transit_local":"10:20","verdict":"unusable","weather_source":"history","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.61,"date":"2026-07-04","moon_free_dark_hours":0.53,"moon_illumination":78,"moon_separation":81.5,"score":0,"score_astronomy":0,"score_weather":94,"transit_alt":72.5,"transit_local":"10:15","verdict":"unusable","weather_source":"history","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.64,"date":"2026-07-05","moon_free_dark_hours":0.88,"moon_illumination":70,"moon_separation":68.7,"score":0,"score_astronomy":0,"score_weather":96,"transit_alt":72.5,"transit_local":"10:10","verdict":"unusable","weather_source":"history","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.67,"date":"2026-07-06","moon_free_dark_hours":1.23,"moon_illumination":59,"moon_separation":55.7,"score":0,"score_astronomy":0,"score_weather":95,"transit_alt":72.5,"transit_local":"10:10","verdict":"unusable","weather_source":"history","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.7,"date":"2026-07-07","moon_free_dark_hours":1.62,"moon_illumination":49,"moon_separation":42.3,"score":0,"score_astronomy":0,"score_weather":99,"transit_alt":72.5,"transit_local":"10:05","verdict":"unusable","weather_source":"history","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.73,"date":"2026-07-08","moon_free_dark_hours":2.07,"moon_illumination":38,"moon_separation":28.6,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":72.5,"transit_local":"10:00","verdict":"unusable","weather_source":"history","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.76,"date":"2026-07-09","moon_free_dark_hours":2.6,"moon_illumination":27,"moon_separation":14.4,"score":1,"score_astronomy":1,"score_weather":96,"transit_alt":72.5,"transit_local":"09:55","verdict":"poor","weather_source":"history","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.8,"date":"2026-07-10","moon_free_dark_hours":3.3,"moon_illumination":17,"moon_separation":1.0,"score":1,"score_astronomy":1,"score_weather":100,"transit_alt":72.5,"transit_local":"09:50","verdict":"poor","weather_source":"history","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.84,"date":"2026-07-11","moon_free_dark_hours":4.18,"moon_illumination":9,"moon_separation":14.9,"score":1,"score_astronomy":1,"score_weather":100,"transit_alt":72.5,"transit_local":"09:50","verdict":"poor","weather_source":"history","weekday":"Sat"},{"best_hours":0.08,"best_label":"marginal","best_window":"04:40\u201304:45","dark_hours":4.87,"date":"2026-07-12","moon_free_dark_hours":4.87,"moon_illumination":3,"moon_separation":30.0,"score":2,"score_astronomy":2,"score_weather":99,"transit_alt":72.5,"transit_local":"09:45","verdict":"poor","weather_source":"history","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":4.91,"date":"2026-07-13","moon_free_dark_hours":4.9,"moon_illumination":0,"moon_separation":45.0,"score":2,"score_astronomy":2,"score_weather":92,"transit_alt":72.5,"transit_local":"09:40","verdict":"poor","weather_source":"history","weekday":"Mon"},{"best_hours":0.25,"best_label":"marginal","best_window":"04:30\u201304:45","dark_hours":4.96,"date":"2026-07-14","moon_free_dark_hours":4.93,"moon_illumination":0,"moon_separation":60.0,"score":2,"score_astronomy":2,"score_weather":99,"transit_alt":72.5,"transit_local":"09:35","verdict":"poor","weather_source":"history","weekday":"Tue"},{"best_hours":0.33,"best_label":"marginal","best_window":"04:30\u201304:50","dark_hours":5.0,"date":"2026-07-15","moon_free_dark_hours":4.98,"moon_illumination":3,"moon_separation":74.8,"score":3,"score_astronomy":3,"score_weather":94,"transit_alt":72.5,"transit_local":"09:35","verdict":"poor","weather_source":"history","weekday":"Wed"},{"best_hours":0.33,"best_label":"marginal","best_window":"04:30\u201304:50","dark_hours":5.04,"date":"2026-07-16","moon_free_dark_hours":5.02,"moon_illumination":9,"moon_separation":89.2,"score":3,"score_astronomy":4,"score_weather":83,"transit_alt":72.5,"transit_local":"09:30","verdict":"poor","weather_source":"history","weekday":"Thu"},{"best_hours":0.5,"best_label":"marginal","best_window":"04:20\u201304:50","dark_hours":5.08,"date":"2026-07-17","moon_free_dark_hours":5.07,"moon_illumination":16,"moon_separation":103.2,"score":5,"score_astronomy":5,"score_weather":99,"transit_alt":72.5,"transit_local":"09:25","verdict":"poor","weather_source":"history","weekday":"Fri"},{"best_hours":0.25,"best_label":"marginal","best_window":"03:50\u201304:05","dark_hours":5.13,"date":"2026-07-18","moon_free_dark_hours":4.9,"moon_illumination":25,"moon_separation":116.8,"score":5,"score_astronomy":6,"score_weather":77,"transit_alt":72.5,"transit_local":"09:20","verdict":"poor","weather_source":"history","weekday":"Sat"},{"best_hours":0.75,"best_label":"marginal","best_window":"04:10\u201304:55","dark_hours":5.18,"date":"2026-07-19","moon_free_dark_hours":4.57,"moon_illumination":35,"moon_separation":129.8,"score":7,"score_astronomy":7,"score_weather":99,"transit_alt":72.5,"transit_local":"09:15","verdict":"poor","weather_source":"history","weekday":"Sun"},{"best_hours":1.25,"best_label":"marginal","best_window":"03:40\u201304:55","dark_hours":5.22,"date":"2026-07-20","moon_free_dark_hours":4.25,"moon_illumination":45,"moon_separation":142.5,"score":8,"score_astronomy":8,"score_weather":96,"transit_alt":72.5,"transit_local":"09:15","verdict":"poor","weather_source":"history","weekday":"Mon"},{"best_hours":0.58,"best_label":"marginal","best_window":"04:20\u201304:55","dark_hours":5.27,"date":"2026-07-21","moon_free_dark_hours":3.87,"moon_illumination":55,"moon_separation":154.8,"score":7,"score_astronomy":11,"score_weather":61,"transit_alt":72.5,"transit_local":"09:10","verdict":"poor","weather_source":"history","weekday":"Tue"},{"best_hours":0.17,"best_label":"good","best_window":"04:00\u201304:10","dark_hours":5.32,"date":"2026-07-22","moon_free_dark_hours":3.47,"moon_illumination":64,"moon_separation":166.9,"score":12,"score_astronomy":12,"score_weather":99,"transit_alt":72.5,"transit_local":"09:05","verdict":"poor","weather_source":"history","weekday":"Wed"},{"best_hours":0.5,"best_label":"marginal","best_window":"03:30\u201304:00","dark_hours":5.37,"date":"2026-07-23","moon_free_dark_hours":2.97,"moon_illumination":73,"moon_separation":178.5,"score":4,"score_astronomy":13,"score_weather":33,"transit_alt":72.5,"transit_local":"09:00","verdict":"poor","weather_source":"history","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":5.42,"date":"2026-07-24","moon_free_dark_hours":2.37,"moon_illumination":81,"moon_separation":169.2,"score":0,"score_astronomy":17,"score_weather":0,"transit_alt":72.5,"transit_local":"08:55","verdict":"unusable","weather_source":"history","weekday":"Fri"},{"best_hours":0.33,"best_label":"good","best_window":"03:55\u201304:15","dark_hours":5.47,"date":"2026-07-25","moon_free_dark_hours":1.62,"moon_illumination":88,"moon_separation":157.4,"score":17,"score_astronomy":19,"score_weather":92,"transit_alt":72.5,"transit_local":"08:55","verdict":"poor","weather_source":"history","weekday":"Sat"},{"best_hours":0.08,"best_label":"good","best_window":"03:55\u201304:00","dark_hours":5.52,"date":"2026-07-26","moon_free_dark_hours":0.75,"moon_illumination":93,"moon_separation":145.5,"score":15,"score_astronomy":20,"score_weather":75,"transit_alt":72.5,"transit_local":"08:50","verdict":"poor","weather_source":"history","weekday":"Sun"},{"best_hours":0.5,"best_label":"good","best_window":"03:50\u201304:20","dark_hours":5.58,"date":"2026-07-27","moon_free_dark_hours":0.0,"moon_illumination":97,"moon_separation":133.6,"score":19,"score_astronomy":19,"score_weather":98,"transit_alt":72.5,"transit_local":"08:45","verdict":"poor","weather_source":"history","weekday":"Mon"},{"best_hours":1.17,"best_label":"marginal","best_window":"03:10\u201304:20","dark_hours":5.63,"date":"2026-07-28","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":121.6,"score":17,"score_astronomy":20,"score_weather":83,"transit_alt":72.5,"transit_local":"08:40","verdict":"poor","weather_source":"history","weekday":"Tue"}],"note":"score_astronomy for every night; score_weather/score only where a forecast (next 4 days) or ERA5 history exists \u2014 null otherwise","start":"2026-06-29","target":{"common_name":"Seven Sisters","dec":24.11388889,"name":"Cl Melotte 22","ra":56.60083333,"simbad_url":"https://simbad.cds.unistra.fr/simbad/sim-id?Ident=M45","source":"sesame","type":"OpC","type_text":"open cluster"}}