{"calculation_version":"2026-10-10.1","days":30,"nights":[{"best_hours":2.75,"best_label":"marginal","best_window":"18:35\u201321:20","dark_hours":11.31,"date":"2039-11-30","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":12.0,"score":null,"score_astronomy":27,"score_weather":null,"transit_alt":72.5,"transit_local":"23:30","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":3.75,"best_label":"marginal","best_window":"18:35\u201322:20","dark_hours":11.33,"date":"2039-12-01","moon_free_dark_hours":0.0,"moon_illumination":99,"moon_separation":23.2,"score":null,"score_astronomy":32,"score_weather":null,"transit_alt":72.5,"transit_local":"23:25","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":6.0,"best_label":"marginal","best_window":"18:35\u201300:35","dark_hours":11.35,"date":"2039-12-02","moon_free_dark_hours":0.0,"moon_illumination":96,"moon_separation":34.8,"score":null,"score_astronomy":45,"score_weather":null,"transit_alt":72.5,"transit_local":"23:25","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.42,"best_label":"good","best_window":"18:35\u201319:00","dark_hours":11.36,"date":"2039-12-03","moon_free_dark_hours":0.47,"moon_illumination":91,"moon_separation":46.6,"score":null,"score_astronomy":82,"score_weather":null,"transit_alt":72.5,"transit_local":"23:20","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":4.75,"best_label":"good","best_window":"18:35\u201323:20","dark_hours":11.38,"date":"2039-12-04","moon_free_dark_hours":1.38,"moon_illumination":85,"moon_separation":58.4,"score":null,"score_astronomy":89,"score_weather":null,"transit_alt":72.5,"transit_local":"23:15","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":7.5,"best_label":"good","best_window":"18:35\u201302:05","dark_hours":11.39,"date":"2039-12-05","moon_free_dark_hours":2.35,"moon_illumination":77,"moon_separation":70.2,"score":null,"score_astronomy":97,"score_weather":null,"transit_alt":72.5,"transit_local":"23:10","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":8.92,"best_label":"good","best_window":"18:35\u201303:30","dark_hours":11.41,"date":"2039-12-06","moon_free_dark_hours":3.38,"moon_illumination":69,"moon_separation":82.3,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"23:10","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":9.33,"best_label":"good","best_window":"18:35\u201303:55","dark_hours":11.42,"date":"2039-12-07","moon_free_dark_hours":4.45,"moon_illumination":59,"moon_separation":94.6,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"23:05","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":9.42,"best_label":"good","best_window":"18:35\u201304:00","dark_hours":11.43,"date":"2039-12-08","moon_free_dark_hours":5.52,"moon_illumination":49,"moon_separation":107.1,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"23:00","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":9.5,"best_label":"good","best_window":"18:35\u201304:05","dark_hours":11.44,"date":"2039-12-09","moon_free_dark_hours":6.62,"moon_illumination":39,"moon_separation":120.0,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:55","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":9.42,"best_label":"good","best_window":"18:35\u201304:00","dark_hours":11.45,"date":"2039-12-10","moon_free_dark_hours":7.77,"moon_illumination":29,"moon_separation":133.3,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:50","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":9.42,"best_label":"good","best_window":"18:35\u201304:00","dark_hours":11.46,"date":"2039-12-11","moon_free_dark_hours":8.95,"moon_illumination":19,"moon_separation":147.1,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:50","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":9.33,"best_label":"good","best_window":"18:35\u201303:55","dark_hours":11.47,"date":"2039-12-12","moon_free_dark_hours":10.22,"moon_illumination":11,"moon_separation":161.1,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:45","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":9.25,"best_label":"good","best_window":"18:35\u201303:50","dark_hours":11.48,"date":"2039-12-13","moon_free_dark_hours":11.45,"moon_illumination":5,"moon_separation":173.7,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:40","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":9.17,"best_label":"good","best_window":"18:35\u201303:45","dark_hours":11.48,"date":"2039-12-14","moon_free_dark_hours":11.47,"moon_illumination":1,"moon_separation":167.1,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:35","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":9.17,"best_label":"good","best_window":"18:35\u201303:45","dark_hours":11.49,"date":"2039-12-15","moon_free_dark_hours":11.48,"moon_illumination":0,"moon_separation":152.5,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:30","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":9.08,"best_label":"good","best_window":"18:35\u201303:40","dark_hours":11.5,"date":"2039-12-16","moon_free_dark_hours":11.48,"moon_illumination":2,"moon_separation":137.4,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:30","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":9.0,"best_label":"good","best_window":"18:35\u201303:35","dark_hours":11.5,"date":"2039-12-17","moon_free_dark_hours":11.38,"moon_illumination":8,"moon_separation":122.4,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:25","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":8.92,"best_label":"good","best_window":"18:35\u201303:30","dark_hours":11.5,"date":"2039-12-18","moon_free_dark_hours":10.13,"moon_illumination":15,"moon_separation":107.8,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:20","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":8.92,"best_label":"good","best_window":"18:35\u201303:30","dark_hours":11.51,"date":"2039-12-19","moon_free_dark_hours":8.88,"moon_illumination":24,"moon_separation":93.5,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:15","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":8.83,"best_label":"good","best_window":"18:35\u201303:25","dark_hours":11.51,"date":"2039-12-20","moon_free_dark_hours":7.67,"moon_illumination":34,"moon_separation":79.7,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:15","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":8.75,"best_label":"good","best_window":"18:35\u201303:20","dark_hours":11.51,"date":"2039-12-21","moon_free_dark_hours":6.52,"moon_illumination":45,"moon_separation":66.3,"score":null,"score_astronomy":100,"score_weather":null,"transit_alt":72.5,"transit_local":"22:10","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":8.67,"best_label":"good","best_window":"18:35\u201303:15","dark_hours":11.51,"date":"2039-12-22","moon_free_dark_hours":5.42,"moon_illumination":55,"moon_separation":53.4,"score":null,"score_astronomy":96,"score_weather":null,"transit_alt":72.5,"transit_local":"22:05","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":6.0,"best_label":"good","best_window":"21:10\u201303:10","dark_hours":11.51,"date":"2039-12-23","moon_free_dark_hours":4.37,"moon_illumination":65,"moon_separation":40.9,"score":null,"score_astronomy":87,"score_weather":null,"transit_alt":72.5,"transit_local":"22:00","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.33,"best_label":"good","best_window":"02:50\u201303:10","dark_hours":11.5,"date":"2039-12-24","moon_free_dark_hours":3.33,"moon_illumination":74,"moon_separation":28.7,"score":null,"score_astronomy":71,"score_weather":null,"transit_alt":72.5,"transit_local":"21:55","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":8.67,"best_label":"marginal","best_window":"18:40\u201303:20","dark_hours":11.5,"date":"2039-12-25","moon_free_dark_hours":2.32,"moon_illumination":82,"moon_separation":16.9,"score":null,"score_astronomy":46,"score_weather":null,"transit_alt":72.5,"transit_local":"21:55","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":8.42,"best_label":"marginal","best_window":"18:40\u201303:05","dark_hours":11.5,"date":"2039-12-26","moon_free_dark_hours":1.3,"moon_illumination":89,"moon_separation":6.7,"score":null,"score_astronomy":32,"score_weather":null,"transit_alt":72.5,"transit_local":"21:50","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":1.83,"best_label":"marginal","best_window":"18:40\u201320:30","dark_hours":11.49,"date":"2039-12-27","moon_free_dark_hours":0.28,"moon_illumination":94,"moon_separation":9.4,"score":null,"score_astronomy":24,"score_weather":null,"transit_alt":72.5,"transit_local":"21:45","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":1.75,"best_label":"marginal","best_window":"18:40\u201320:25","dark_hours":11.49,"date":"2039-12-28","moon_free_dark_hours":0.0,"moon_illumination":98,"moon_separation":20.4,"score":null,"score_astronomy":22,"score_weather":null,"transit_alt":72.5,"transit_local":"21:40","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":2.42,"best_label":"marginal","best_window":"18:40\u201321:05","dark_hours":11.48,"date":"2039-12-29","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":31.9,"score":null,"score_astronomy":25,"score_weather":null,"transit_alt":72.5,"transit_local":"21:35","verdict":"unknown","weather_source":"none","weekday":"Thu"}],"note":"score_astronomy for every night; score_weather/score only where a forecast (next 4 days) or ERA5 history exists \u2014 null otherwise","start":"2039-11-30","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"}}