{"calculation_version":"2026-10-10.1","days":30,"nights":[{"best_hours":1.17,"best_label":"good","best_window":"20:10\u201321:20","dark_hours":8.7,"date":"2028-03-20","moon_free_dark_hours":8.05,"moon_illumination":23,"moon_separation":131.9,"score":null,"score_astronomy":31,"score_weather":null,"transit_alt":42.9,"transit_local":"18:05","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":1.17,"best_label":"good","best_window":"20:10\u201321:20","dark_hours":8.64,"date":"2028-03-21","moon_free_dark_hours":8.45,"moon_illumination":16,"moon_separation":123.0,"score":null,"score_astronomy":29,"score_weather":null,"transit_alt":42.9,"transit_local":"18:00","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":1.08,"best_label":"good","best_window":"20:10\u201321:15","dark_hours":8.59,"date":"2028-03-22","moon_free_dark_hours":8.58,"moon_illumination":9,"moon_separation":113.5,"score":null,"score_astronomy":28,"score_weather":null,"transit_alt":42.9,"transit_local":"17:55","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.92,"best_label":"good","best_window":"20:15\u201321:10","dark_hours":8.54,"date":"2028-03-23","moon_free_dark_hours":8.53,"moon_illumination":5,"moon_separation":103.7,"score":null,"score_astronomy":26,"score_weather":null,"transit_alt":42.9,"transit_local":"17:50","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.83,"best_label":"good","best_window":"20:15\u201321:05","dark_hours":8.49,"date":"2028-03-24","moon_free_dark_hours":8.47,"moon_illumination":2,"moon_separation":93.7,"score":null,"score_astronomy":24,"score_weather":null,"transit_alt":42.9,"transit_local":"17:45","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.75,"best_label":"good","best_window":"20:15\u201321:00","dark_hours":8.43,"date":"2028-03-25","moon_free_dark_hours":8.42,"moon_illumination":0,"moon_separation":83.5,"score":null,"score_astronomy":23,"score_weather":null,"transit_alt":42.9,"transit_local":"17:45","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.75,"best_label":"good","best_window":"21:15\u201322:00","dark_hours":8.38,"date":"2028-03-26","moon_free_dark_hours":8.37,"moon_illumination":1,"moon_separation":73.2,"score":null,"score_astronomy":22,"score_weather":null,"transit_alt":42.9,"transit_local":"18:40","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.58,"best_label":"good","best_window":"21:20\u201321:55","dark_hours":8.33,"date":"2028-03-27","moon_free_dark_hours":8.3,"moon_illumination":3,"moon_separation":63.1,"score":null,"score_astronomy":19,"score_weather":null,"transit_alt":42.9,"transit_local":"18:35","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.5,"best_label":"good","best_window":"21:20\u201321:50","dark_hours":8.27,"date":"2028-03-28","moon_free_dark_hours":7.28,"moon_illumination":7,"moon_separation":53.4,"score":null,"score_astronomy":16,"score_weather":null,"transit_alt":42.9,"transit_local":"18:30","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.33,"best_label":"good","best_window":"21:20\u201321:40","dark_hours":8.22,"date":"2028-03-29","moon_free_dark_hours":6.15,"moon_illumination":13,"moon_separation":44.4,"score":null,"score_astronomy":14,"score_weather":null,"transit_alt":42.9,"transit_local":"18:25","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.08,"best_label":"good","best_window":"21:25\u201321:30","dark_hours":8.16,"date":"2028-03-30","moon_free_dark_hours":5.03,"moon_illumination":21,"moon_separation":36.9,"score":null,"score_astronomy":10,"score_weather":null,"transit_alt":42.9,"transit_local":"18:25","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.75,"best_label":"marginal","best_window":"21:25\u201322:10","dark_hours":8.11,"date":"2028-03-31","moon_free_dark_hours":3.98,"moon_illumination":30,"moon_separation":32.3,"score":null,"score_astronomy":8,"score_weather":null,"transit_alt":42.9,"transit_local":"18:20","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.67,"best_label":"marginal","best_window":"21:25\u201322:05","dark_hours":8.05,"date":"2028-04-01","moon_free_dark_hours":3.03,"moon_illumination":40,"moon_separation":32.1,"score":null,"score_astronomy":5,"score_weather":null,"transit_alt":42.9,"transit_local":"18:15","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.42,"best_label":"marginal","best_window":"21:25\u201321:50","dark_hours":8.0,"date":"2028-04-02","moon_free_dark_hours":2.23,"moon_illumination":51,"moon_separation":36.8,"score":null,"score_astronomy":4,"score_weather":null,"transit_alt":42.9,"transit_local":"18:10","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.17,"best_label":"marginal","best_window":"21:30\u201321:40","dark_hours":7.94,"date":"2028-04-03","moon_free_dark_hours":1.53,"moon_illumination":63,"moon_separation":45.0,"score":null,"score_astronomy":2,"score_weather":null,"transit_alt":42.9,"transit_local":"18:10","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.08,"best_label":"marginal","best_window":"21:30\u201321:35","dark_hours":7.89,"date":"2028-04-04","moon_free_dark_hours":0.93,"moon_illumination":73,"moon_separation":55.4,"score":null,"score_astronomy":2,"score_weather":null,"transit_alt":42.9,"transit_local":"18:05","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.08,"best_label":"marginal","best_window":"21:30\u201321:35","dark_hours":7.83,"date":"2028-04-05","moon_free_dark_hours":0.4,"moon_illumination":83,"moon_separation":67.0,"score":null,"score_astronomy":2,"score_weather":null,"transit_alt":42.9,"transit_local":"18:00","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.08,"best_label":"marginal","best_window":"21:30\u201321:35","dark_hours":7.78,"date":"2028-04-06","moon_free_dark_hours":0.0,"moon_illumination":91,"moon_separation":79.4,"score":null,"score_astronomy":2,"score_weather":null,"transit_alt":42.9,"transit_local":"17:55","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.08,"best_label":"marginal","best_window":"21:35\u201321:40","dark_hours":7.72,"date":"2028-04-07","moon_free_dark_hours":0.0,"moon_illumination":97,"moon_separation":92.1,"score":null,"score_astronomy":2,"score_weather":null,"transit_alt":42.9,"transit_local":"17:50","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.08,"best_label":"marginal","best_window":"21:35\u201321:40","dark_hours":7.66,"date":"2028-04-08","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":104.7,"score":null,"score_astronomy":2,"score_weather":null,"transit_alt":42.9,"transit_local":"17:50","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.61,"date":"2028-04-09","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":116.9,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":42.9,"transit_local":"17:45","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.55,"date":"2028-04-10","moon_free_dark_hours":0.15,"moon_illumination":97,"moon_separation":128.2,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":42.9,"transit_local":"17:40","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.49,"date":"2028-04-11","moon_free_dark_hours":1.38,"moon_illumination":92,"moon_separation":137.9,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":42.9,"transit_local":"17:35","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.44,"date":"2028-04-12","moon_free_dark_hours":2.5,"moon_illumination":85,"moon_separation":145.1,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":42.9,"transit_local":"17:30","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.38,"date":"2028-04-13","moon_free_dark_hours":3.47,"moon_illumination":76,"moon_separation":148.4,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":42.9,"transit_local":"17:30","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.32,"date":"2028-04-14","moon_free_dark_hours":4.27,"moon_illumination":67,"moon_separation":147.1,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":42.9,"transit_local":"17:25","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.26,"date":"2028-04-15","moon_free_dark_hours":4.93,"moon_illumination":57,"moon_separation":142.0,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":42.9,"transit_local":"17:20","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.21,"date":"2028-04-16","moon_free_dark_hours":5.43,"moon_illumination":48,"moon_separation":134.6,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":42.9,"transit_local":"17:15","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.15,"date":"2028-04-17","moon_free_dark_hours":5.88,"moon_illumination":38,"moon_separation":125.9,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":42.9,"transit_local":"17:15","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.09,"date":"2028-04-18","moon_free_dark_hours":6.23,"moon_illumination":29,"moon_separation":116.5,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":42.9,"transit_local":"17:10","verdict":"unknown","weather_source":"none","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":"2028-03-20","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"}}