{"calculation_version":"2026-10-10.1","days":30,"nights":[{"best_hours":1.58,"best_label":"good","best_window":"03:55\u201305:30","dark_hours":8.45,"date":"2028-09-16","moon_free_dark_hours":8.25,"moon_illumination":5,"moon_separation":67.0,"score":null,"score_astronomy":38,"score_weather":null,"transit_alt":42.9,"transit_local":"07:10","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":1.67,"best_label":"good","best_window":"03:55\u201305:35","dark_hours":8.5,"date":"2028-09-17","moon_free_dark_hours":8.48,"moon_illumination":1,"moon_separation":79.8,"score":null,"score_astronomy":41,"score_weather":null,"transit_alt":42.9,"transit_local":"07:05","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":1.75,"best_label":"good","best_window":"03:50\u201305:35","dark_hours":8.56,"date":"2028-09-18","moon_free_dark_hours":8.53,"moon_illumination":0,"moon_separation":92.8,"score":null,"score_astronomy":42,"score_weather":null,"transit_alt":42.9,"transit_local":"07:05","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":1.83,"best_label":"good","best_window":"03:45\u201305:35","dark_hours":8.61,"date":"2028-09-19","moon_free_dark_hours":8.6,"moon_illumination":2,"moon_separation":105.8,"score":null,"score_astronomy":43,"score_weather":null,"transit_alt":42.9,"transit_local":"07:00","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":1.92,"best_label":"good","best_window":"03:40\u201305:35","dark_hours":8.66,"date":"2028-09-20","moon_free_dark_hours":8.65,"moon_illumination":7,"moon_separation":118.3,"score":null,"score_astronomy":45,"score_weather":null,"transit_alt":42.9,"transit_local":"06:55","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":2.08,"best_label":"good","best_window":"03:35\u201305:40","dark_hours":8.71,"date":"2028-09-21","moon_free_dark_hours":8.7,"moon_illumination":14,"moon_separation":129.7,"score":null,"score_astronomy":48,"score_weather":null,"transit_alt":42.9,"transit_local":"06:50","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":2.08,"best_label":"good","best_window":"03:35\u201305:40","dark_hours":8.76,"date":"2028-09-22","moon_free_dark_hours":8.52,"moon_illumination":23,"moon_separation":139.5,"score":null,"score_astronomy":48,"score_weather":null,"transit_alt":42.9,"transit_local":"06:50","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":2.17,"best_label":"good","best_window":"03:30\u201305:40","dark_hours":8.81,"date":"2028-09-23","moon_free_dark_hours":7.72,"moon_illumination":33,"moon_separation":146.4,"score":null,"score_astronomy":50,"score_weather":null,"transit_alt":42.9,"transit_local":"06:45","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":2.25,"best_label":"good","best_window":"03:25\u201305:40","dark_hours":8.86,"date":"2028-09-24","moon_free_dark_hours":6.82,"moon_illumination":44,"moon_separation":149.1,"score":null,"score_astronomy":52,"score_weather":null,"transit_alt":42.9,"transit_local":"06:40","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":2.42,"best_label":"good","best_window":"03:20\u201305:45","dark_hours":8.91,"date":"2028-09-25","moon_free_dark_hours":5.85,"moon_illumination":54,"moon_separation":147.0,"score":null,"score_astronomy":55,"score_weather":null,"transit_alt":42.9,"transit_local":"06:35","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":2.42,"best_label":"good","best_window":"03:20\u201305:45","dark_hours":8.96,"date":"2028-09-26","moon_free_dark_hours":4.8,"moon_illumination":64,"moon_separation":141.3,"score":null,"score_astronomy":56,"score_weather":null,"transit_alt":42.9,"transit_local":"06:30","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":2.5,"best_label":"good","best_window":"03:15\u201305:45","dark_hours":9.01,"date":"2028-09-27","moon_free_dark_hours":3.77,"moon_illumination":73,"moon_separation":133.4,"score":null,"score_astronomy":57,"score_weather":null,"transit_alt":42.9,"transit_local":"06:30","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":2.58,"best_label":"good","best_window":"03:10\u201305:45","dark_hours":9.06,"date":"2028-09-28","moon_free_dark_hours":2.73,"moon_illumination":81,"moon_separation":124.3,"score":null,"score_astronomy":59,"score_weather":null,"transit_alt":42.9,"transit_local":"06:25","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":2.5,"best_label":"good","best_window":"03:15\u201305:45","dark_hours":9.11,"date":"2028-09-29","moon_free_dark_hours":1.73,"moon_illumination":88,"moon_separation":114.7,"score":null,"score_astronomy":58,"score_weather":null,"transit_alt":42.9,"transit_local":"06:20","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":2.5,"best_label":"good","best_window":"03:20\u201305:50","dark_hours":9.16,"date":"2028-09-30","moon_free_dark_hours":0.75,"moon_illumination":93,"moon_separation":104.8,"score":null,"score_astronomy":57,"score_weather":null,"transit_alt":42.9,"transit_local":"06:15","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":2.33,"best_label":"good","best_window":"03:30\u201305:50","dark_hours":9.2,"date":"2028-10-01","moon_free_dark_hours":0.0,"moon_illumination":97,"moon_separation":94.7,"score":null,"score_astronomy":43,"score_weather":null,"transit_alt":42.9,"transit_local":"06:10","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":1.25,"best_label":"good","best_window":"04:35\u201305:50","dark_hours":9.25,"date":"2028-10-02","moon_free_dark_hours":0.0,"moon_illumination":99,"moon_separation":84.5,"score":null,"score_astronomy":35,"score_weather":null,"transit_alt":42.9,"transit_local":"06:10","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":3.17,"best_label":"marginal","best_window":"02:40\u201305:50","dark_hours":9.3,"date":"2028-10-03","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":74.4,"score":null,"score_astronomy":27,"score_weather":null,"transit_alt":42.9,"transit_local":"06:05","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":3.08,"best_label":"marginal","best_window":"02:50\u201305:55","dark_hours":9.35,"date":"2028-10-04","moon_free_dark_hours":0.0,"moon_illumination":98,"moon_separation":64.4,"score":null,"score_astronomy":21,"score_weather":null,"transit_alt":42.9,"transit_local":"06:00","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":2.92,"best_label":"marginal","best_window":"03:00\u201305:55","dark_hours":9.39,"date":"2028-10-05","moon_free_dark_hours":0.0,"moon_illumination":95,"moon_separation":54.7,"score":null,"score_astronomy":16,"score_weather":null,"transit_alt":42.9,"transit_local":"05:55","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":2.83,"best_label":"marginal","best_window":"03:05\u201305:55","dark_hours":9.44,"date":"2028-10-06","moon_free_dark_hours":0.0,"moon_illumination":90,"moon_separation":45.6,"score":null,"score_astronomy":13,"score_weather":null,"transit_alt":42.9,"transit_local":"05:55","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":2.92,"best_label":"marginal","best_window":"03:00\u201305:55","dark_hours":9.49,"date":"2028-10-07","moon_free_dark_hours":0.18,"moon_illumination":84,"moon_separation":37.8,"score":null,"score_astronomy":12,"score_weather":null,"transit_alt":42.9,"transit_local":"05:50","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":3.25,"best_label":"marginal","best_window":"02:40\u201305:55","dark_hours":9.53,"date":"2028-10-08","moon_free_dark_hours":0.98,"moon_illumination":76,"moon_separation":32.3,"score":null,"score_astronomy":14,"score_weather":null,"transit_alt":42.9,"transit_local":"05:45","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":3.75,"best_label":"marginal","best_window":"02:15\u201306:00","dark_hours":9.58,"date":"2028-10-09","moon_free_dark_hours":1.9,"moon_illumination":66,"moon_separation":30.8,"score":null,"score_astronomy":20,"score_weather":null,"transit_alt":42.9,"transit_local":"05:40","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":4.08,"best_label":"marginal","best_window":"01:55\u201306:00","dark_hours":9.62,"date":"2028-10-10","moon_free_dark_hours":2.98,"moon_illumination":56,"moon_separation":34.0,"score":null,"score_astronomy":29,"score_weather":null,"transit_alt":42.9,"transit_local":"05:35","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":3.17,"best_label":"good","best_window":"02:50\u201306:00","dark_hours":9.67,"date":"2028-10-11","moon_free_dark_hours":4.15,"moon_illumination":45,"moon_separation":41.2,"score":null,"score_astronomy":43,"score_weather":null,"transit_alt":42.9,"transit_local":"05:35","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":3.5,"best_label":"good","best_window":"02:30\u201306:00","dark_hours":9.71,"date":"2028-10-12","moon_free_dark_hours":5.38,"moon_illumination":34,"moon_separation":50.8,"score":null,"score_astronomy":57,"score_weather":null,"transit_alt":42.9,"transit_local":"05:30","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":3.92,"best_label":"good","best_window":"02:10\u201306:05","dark_hours":9.76,"date":"2028-10-13","moon_free_dark_hours":6.65,"moon_illumination":24,"moon_separation":62.0,"score":null,"score_astronomy":71,"score_weather":null,"transit_alt":42.9,"transit_local":"05:25","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":4.0,"best_label":"good","best_window":"02:05\u201306:05","dark_hours":9.8,"date":"2028-10-14","moon_free_dark_hours":7.93,"moon_illumination":15,"moon_separation":74.2,"score":null,"score_astronomy":82,"score_weather":null,"transit_alt":42.9,"transit_local":"05:20","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":4.0,"best_label":"good","best_window":"02:05\u201306:05","dark_hours":9.84,"date":"2028-10-15","moon_free_dark_hours":9.23,"moon_illumination":7,"moon_separation":86.9,"score":null,"score_astronomy":87,"score_weather":null,"transit_alt":42.9,"transit_local":"05:15","verdict":"unknown","weather_source":"none","weekday":"Sun"}],"note":"score_astronomy for every night; score_weather/score only where a forecast (next 4 days) or ERA5 history exists \u2014 null otherwise","start":"2028-09-16","target":{"common_name":"Great Orion Nebula","dec":-5.3876,"name":"M 42","ra":83.8201,"simbad_url":"https://simbad.cds.unistra.fr/simbad/sim-id?Ident=M42","source":"sesame","type":"HII","type_text":"HII region \u2014 a star-forming nebula"}}