{"calculation_version":"2026-10-10.1","days":30,"nights":[{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":8.45,"date":"2025-03-25","moon_free_dark_hours":8.42,"moon_illumination":17,"moon_separation":75.6,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.5,"transit_local":"12:55","verdict":"unusable","weather_source":"history","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":8.39,"date":"2025-03-26","moon_free_dark_hours":8.38,"moon_illumination":9,"moon_separation":63.7,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.6,"transit_local":"12:50","verdict":"unusable","weather_source":"history","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":8.34,"date":"2025-03-27","moon_free_dark_hours":8.33,"moon_illumination":3,"moon_separation":52.0,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.7,"transit_local":"12:45","verdict":"unusable","weather_source":"history","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":8.29,"date":"2025-03-28","moon_free_dark_hours":8.27,"moon_illumination":0,"moon_separation":41.4,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.7,"transit_local":"12:40","verdict":"unusable","weather_source":"history","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":8.23,"date":"2025-03-29","moon_free_dark_hours":8.22,"moon_illumination":0,"moon_separation":33.4,"score":0,"score_astronomy":0,"score_weather":32,"transit_alt":89.6,"transit_local":"12:35","verdict":"unusable","weather_source":"history","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":8.18,"date":"2025-03-30","moon_free_dark_hours":8.17,"moon_illumination":3,"moon_separation":30.6,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.5,"transit_local":"13:35","verdict":"unusable","weather_source":"history","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":8.12,"date":"2025-03-31","moon_free_dark_hours":6.85,"moon_illumination":9,"moon_separation":34.1,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.7,"transit_local":"13:30","verdict":"unusable","weather_source":"history","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":8.07,"date":"2025-04-01","moon_free_dark_hours":5.47,"moon_illumination":17,"moon_separation":42.2,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.7,"transit_local":"13:25","verdict":"unusable","weather_source":"history","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":8.01,"date":"2025-04-02","moon_free_dark_hours":4.15,"moon_illumination":27,"moon_separation":52.5,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.6,"transit_local":"13:20","verdict":"unusable","weather_source":"history","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.96,"date":"2025-04-03","moon_free_dark_hours":3.0,"moon_illumination":37,"moon_separation":63.7,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.5,"transit_local":"13:15","verdict":"unusable","weather_source":"history","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.9,"date":"2025-04-04","moon_free_dark_hours":2.05,"moon_illumination":48,"moon_separation":75.1,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.6,"transit_local":"13:15","verdict":"unusable","weather_source":"history","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.85,"date":"2025-04-05","moon_free_dark_hours":1.32,"moon_illumination":59,"moon_separation":86.5,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.7,"transit_local":"13:10","verdict":"unusable","weather_source":"history","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.79,"date":"2025-04-06","moon_free_dark_hours":0.73,"moon_illumination":69,"moon_separation":97.5,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.7,"transit_local":"13:05","verdict":"unusable","weather_source":"history","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.74,"date":"2025-04-07","moon_free_dark_hours":0.27,"moon_illumination":78,"moon_separation":108.3,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.6,"transit_local":"13:00","verdict":"unusable","weather_source":"history","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.68,"date":"2025-04-08","moon_free_dark_hours":0.0,"moon_illumination":85,"moon_separation":118.5,"score":0,"score_astronomy":0,"score_weather":99,"transit_alt":89.5,"transit_local":"13:00","verdict":"unusable","weather_source":"history","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.62,"date":"2025-04-09","moon_free_dark_hours":0.0,"moon_illumination":92,"moon_separation":128.2,"score":0,"score_astronomy":0,"score_weather":96,"transit_alt":89.6,"transit_local":"12:55","verdict":"unusable","weather_source":"history","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.57,"date":"2025-04-10","moon_free_dark_hours":0.0,"moon_illumination":96,"moon_separation":136.9,"score":0,"score_astronomy":0,"score_weather":94,"transit_alt":89.7,"transit_local":"12:50","verdict":"unusable","weather_source":"history","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.51,"date":"2025-04-11","moon_free_dark_hours":0.0,"moon_illumination":99,"moon_separation":144.0,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.7,"transit_local":"12:45","verdict":"unusable","weather_source":"history","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.45,"date":"2025-04-12","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":148.4,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.6,"transit_local":"12:40","verdict":"unusable","weather_source":"history","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.39,"date":"2025-04-13","moon_free_dark_hours":0.0,"moon_illumination":99,"moon_separation":149.2,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.5,"transit_local":"12:40","verdict":"unusable","weather_source":"history","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.34,"date":"2025-04-14","moon_free_dark_hours":0.17,"moon_illumination":97,"moon_separation":146.1,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.6,"transit_local":"12:35","verdict":"unusable","weather_source":"history","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.28,"date":"2025-04-15","moon_free_dark_hours":1.22,"moon_illumination":92,"moon_separation":139.9,"score":0,"score_astronomy":0,"score_weather":72,"transit_alt":89.7,"transit_local":"12:30","verdict":"unusable","weather_source":"history","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.22,"date":"2025-04-16","moon_free_dark_hours":2.27,"moon_illumination":87,"moon_separation":131.8,"score":0,"score_astronomy":0,"score_weather":78,"transit_alt":89.7,"transit_local":"12:25","verdict":"unusable","weather_source":"history","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.16,"date":"2025-04-17","moon_free_dark_hours":3.25,"moon_illumination":79,"moon_separation":122.5,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.5,"transit_local":"12:20","verdict":"unusable","weather_source":"history","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.11,"date":"2025-04-18","moon_free_dark_hours":4.13,"moon_illumination":71,"moon_separation":112.6,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.6,"transit_local":"12:20","verdict":"unusable","weather_source":"history","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":7.05,"date":"2025-04-19","moon_free_dark_hours":4.88,"moon_illumination":62,"moon_separation":102.0,"score":0,"score_astronomy":0,"score_weather":0,"transit_alt":89.7,"transit_local":"12:15","verdict":"unusable","weather_source":"history","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.99,"date":"2025-04-20","moon_free_dark_hours":5.5,"moon_illumination":52,"moon_separation":91.1,"score":0,"score_astronomy":0,"score_weather":87,"transit_alt":89.7,"transit_local":"12:10","verdict":"unusable","weather_source":"history","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.93,"date":"2025-04-21","moon_free_dark_hours":6.0,"moon_illumination":41,"moon_separation":79.9,"score":0,"score_astronomy":0,"score_weather":64,"transit_alt":89.6,"transit_local":"12:05","verdict":"unusable","weather_source":"history","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.87,"date":"2025-04-22","moon_free_dark_hours":6.43,"moon_illumination":30,"moon_separation":68.4,"score":0,"score_astronomy":0,"score_weather":88,"transit_alt":89.6,"transit_local":"12:00","verdict":"unusable","weather_source":"history","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":6.81,"date":"2025-04-23","moon_free_dark_hours":6.8,"moon_illumination":21,"moon_separation":56.9,"score":0,"score_astronomy":0,"score_weather":77,"transit_alt":89.7,"transit_local":"11:55","verdict":"unusable","weather_source":"history","weekday":"Wed"}],"note":"score_astronomy for every night; score_weather/score only where a forecast (next 4 days) or ERA5 history exists \u2014 null otherwise","start":"2025-03-25","target":{"common_name":"Andromeda Galaxy","dec":41.26875,"morphology":"SA(s)b","name":"M 31","ra":10.68470833,"simbad_url":"https://simbad.cds.unistra.fr/simbad/sim-id?Ident=M31","source":"sesame","type":"AGN","type_text":"galaxy with an active nucleus","vmag":3.44}}
