{"calculation_version":"2026-10-10.1","days":30,"nights":[{"best_hours":0.25,"best_label":"marginal","best_window":"21:00\u201321:15","dark_hours":7.73,"date":"2029-04-07","moon_free_dark_hours":6.72,"moon_illumination":29,"moon_separation":106.7,"score":null,"score_astronomy":3,"score_weather":null,"transit_alt":72.5,"transit_local":"16:05","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.17,"best_label":"marginal","best_window":"21:00\u201321:10","dark_hours":7.68,"date":"2029-04-08","moon_free_dark_hours":7.1,"moon_illumination":21,"moon_separation":94.5,"score":null,"score_astronomy":3,"score_weather":null,"transit_alt":72.5,"transit_local":"16:00","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.17,"best_label":"marginal","best_window":"21:00\u201321:10","dark_hours":7.62,"date":"2029-04-09","moon_free_dark_hours":7.47,"moon_illumination":14,"moon_separation":82.5,"score":null,"score_astronomy":2,"score_weather":null,"transit_alt":72.5,"transit_local":"15:55","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.08,"best_label":"marginal","best_window":"21:00\u201321:05","dark_hours":7.56,"date":"2029-04-10","moon_free_dark_hours":7.53,"moon_illumination":8,"moon_separation":70.6,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":72.5,"transit_local":"15:55","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.51,"date":"2029-04-11","moon_free_dark_hours":7.48,"moon_illumination":4,"moon_separation":58.7,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":72.5,"transit_local":"15:50","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.45,"date":"2029-04-12","moon_free_dark_hours":7.43,"moon_illumination":1,"moon_separation":46.9,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":72.5,"transit_local":"15:45","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.39,"date":"2029-04-13","moon_free_dark_hours":7.37,"moon_illumination":0,"moon_separation":35.1,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":72.5,"transit_local":"15:40","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.33,"date":"2029-04-14","moon_free_dark_hours":7.32,"moon_illumination":1,"moon_separation":23.2,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":72.5,"transit_local":"15:35","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.28,"date":"2029-04-15","moon_free_dark_hours":7.17,"moon_illumination":4,"moon_separation":11.3,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"15:35","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.22,"date":"2029-04-16","moon_free_dark_hours":6.17,"moon_illumination":8,"moon_separation":1.3,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"15:30","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.16,"date":"2029-04-17","moon_free_dark_hours":5.18,"moon_illumination":14,"moon_separation":12.9,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"15:25","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.1,"date":"2029-04-18","moon_free_dark_hours":4.27,"moon_illumination":22,"moon_separation":25.3,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"15:20","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.05,"date":"2029-04-19","moon_free_dark_hours":3.45,"moon_illumination":31,"moon_separation":37.8,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"15:20","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.99,"date":"2029-04-20","moon_free_dark_hours":2.73,"moon_illumination":40,"moon_separation":50.7,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"15:15","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.93,"date":"2029-04-21","moon_free_dark_hours":2.1,"moon_illumination":51,"moon_separation":63.9,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"15:10","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.87,"date":"2029-04-22","moon_free_dark_hours":1.55,"moon_illumination":62,"moon_separation":77.5,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"15:05","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.81,"date":"2029-04-23","moon_free_dark_hours":1.02,"moon_illumination":73,"moon_separation":91.5,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"15:00","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.75,"date":"2029-04-24","moon_free_dark_hours":0.52,"moon_illumination":82,"moon_separation":105.9,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"15:00","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.7,"date":"2029-04-25","moon_free_dark_hours":0.0,"moon_illumination":90,"moon_separation":120.7,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:55","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.64,"date":"2029-04-26","moon_free_dark_hours":0.0,"moon_illumination":96,"moon_separation":135.8,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:50","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.58,"date":"2029-04-27","moon_free_dark_hours":0.0,"moon_illumination":99,"moon_separation":151.0,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:45","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.52,"date":"2029-04-28","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":166.1,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:40","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.46,"date":"2029-04-29","moon_free_dark_hours":0.03,"moon_illumination":97,"moon_separation":178.5,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:40","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.41,"date":"2029-04-30","moon_free_dark_hours":1.18,"moon_illumination":91,"moon_separation":164.2,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:35","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.35,"date":"2029-05-01","moon_free_dark_hours":2.13,"moon_illumination":84,"moon_separation":150.1,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:30","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.29,"date":"2029-05-02","moon_free_dark_hours":2.9,"moon_illumination":75,"moon_separation":136.4,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:25","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.23,"date":"2029-05-03","moon_free_dark_hours":3.53,"moon_illumination":65,"moon_separation":123.1,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:25","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.17,"date":"2029-05-04","moon_free_dark_hours":4.03,"moon_illumination":55,"moon_separation":110.3,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:20","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.12,"date":"2029-05-05","moon_free_dark_hours":4.47,"moon_illumination":45,"moon_separation":97.8,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:15","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.06,"date":"2029-05-06","moon_free_dark_hours":4.83,"moon_illumination":35,"moon_separation":85.7,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":72.5,"transit_local":"14:10","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":"2029-04-07","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"}}