{"calculation_version":"2026-10-10.1","days":30,"nights":[{"best_hours":1.33,"best_label":"good","best_window":"03:40\u201305:00","dark_hours":8.9,"date":"2040-03-16","moon_free_dark_hours":6.7,"moon_illumination":16,"moon_separation":95.6,"score":null,"score_astronomy":34,"score_weather":null,"transit_alt":71.1,"transit_local":"08:40","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":1.33,"best_label":"good","best_window":"03:35\u201304:55","dark_hours":8.84,"date":"2040-03-17","moon_free_dark_hours":5.62,"moon_illumination":24,"moon_separation":104.0,"score":null,"score_astronomy":34,"score_weather":null,"transit_alt":71.1,"transit_local":"08:40","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":1.42,"best_label":"good","best_window":"03:30\u201304:55","dark_hours":8.79,"date":"2040-03-18","moon_free_dark_hours":4.52,"moon_illumination":33,"moon_separation":111.8,"score":null,"score_astronomy":36,"score_weather":null,"transit_alt":71.1,"transit_local":"08:35","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":1.42,"best_label":"good","best_window":"03:30\u201304:55","dark_hours":8.74,"date":"2040-03-19","moon_free_dark_hours":3.48,"moon_illumination":42,"moon_separation":118.9,"score":null,"score_astronomy":37,"score_weather":null,"transit_alt":71.1,"transit_local":"08:30","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":1.42,"best_label":"good","best_window":"03:25\u201304:50","dark_hours":8.69,"date":"2040-03-20","moon_free_dark_hours":2.52,"moon_illumination":52,"moon_separation":125.0,"score":null,"score_astronomy":37,"score_weather":null,"transit_alt":71.1,"transit_local":"08:25","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":1.5,"best_label":"good","best_window":"03:20\u201304:50","dark_hours":8.64,"date":"2040-03-21","moon_free_dark_hours":1.65,"moon_illumination":61,"moon_separation":129.7,"score":null,"score_astronomy":38,"score_weather":null,"transit_alt":71.1,"transit_local":"08:20","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":1.42,"best_label":"good","best_window":"03:20\u201304:45","dark_hours":8.59,"date":"2040-03-22","moon_free_dark_hours":0.88,"moon_illumination":70,"moon_separation":132.6,"score":null,"score_astronomy":37,"score_weather":null,"transit_alt":71.1,"transit_local":"08:20","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":1.42,"best_label":"good","best_window":"03:20\u201304:45","dark_hours":8.53,"date":"2040-03-23","moon_free_dark_hours":0.25,"moon_illumination":78,"moon_separation":133.3,"score":null,"score_astronomy":37,"score_weather":null,"transit_alt":71.1,"transit_local":"08:15","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":1.5,"best_label":"good","best_window":"04:15\u201305:45","dark_hours":8.48,"date":"2040-03-24","moon_free_dark_hours":0.0,"moon_illumination":86,"moon_separation":131.7,"score":null,"score_astronomy":35,"score_weather":null,"transit_alt":71.1,"transit_local":"09:10","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":1.42,"best_label":"good","best_window":"04:15\u201305:40","dark_hours":8.43,"date":"2040-03-25","moon_free_dark_hours":0.0,"moon_illumination":92,"moon_separation":127.7,"score":null,"score_astronomy":33,"score_weather":null,"transit_alt":71.1,"transit_local":"09:05","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":1.5,"best_label":"good","best_window":"04:10\u201305:40","dark_hours":8.37,"date":"2040-03-26","moon_free_dark_hours":0.0,"moon_illumination":97,"moon_separation":121.9,"score":null,"score_astronomy":34,"score_weather":null,"transit_alt":71.1,"transit_local":"09:00","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":1.5,"best_label":"good","best_window":"04:10\u201305:40","dark_hours":8.32,"date":"2040-03-27","moon_free_dark_hours":0.0,"moon_illumination":99,"moon_separation":114.6,"score":null,"score_astronomy":32,"score_weather":null,"transit_alt":71.1,"transit_local":"09:00","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":1.33,"best_label":"good","best_window":"04:15\u201305:35","dark_hours":8.27,"date":"2040-03-28","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":106.2,"score":null,"score_astronomy":29,"score_weather":null,"transit_alt":71.1,"transit_local":"08:55","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":1.33,"best_label":"good","best_window":"04:15\u201305:35","dark_hours":8.21,"date":"2040-03-29","moon_free_dark_hours":0.0,"moon_illumination":98,"moon_separation":97.1,"score":null,"score_astronomy":26,"score_weather":null,"transit_alt":71.1,"transit_local":"08:50","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.83,"best_label":"good","best_window":"04:40\u201305:30","dark_hours":8.16,"date":"2040-03-30","moon_free_dark_hours":0.67,"moon_illumination":94,"moon_separation":87.6,"score":null,"score_astronomy":24,"score_weather":null,"transit_alt":71.1,"transit_local":"08:45","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.67,"best_label":"good","best_window":"04:50\u201305:30","dark_hours":8.1,"date":"2040-03-31","moon_free_dark_hours":1.87,"moon_illumination":87,"moon_separation":78.2,"score":null,"score_astronomy":23,"score_weather":null,"transit_alt":71.1,"transit_local":"08:45","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.83,"best_label":"good","best_window":"04:40\u201305:30","dark_hours":8.05,"date":"2040-04-01","moon_free_dark_hours":3.1,"moon_illumination":79,"moon_separation":69.0,"score":null,"score_astronomy":24,"score_weather":null,"transit_alt":71.1,"transit_local":"08:40","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":1.33,"best_label":"good","best_window":"04:05\u201305:25","dark_hours":7.99,"date":"2040-04-02","moon_free_dark_hours":4.28,"moon_illumination":68,"moon_separation":60.7,"score":null,"score_astronomy":26,"score_weather":null,"transit_alt":71.1,"transit_local":"08:35","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":1.58,"best_label":"good","best_window":"03:50\u201305:25","dark_hours":7.94,"date":"2040-04-03","moon_free_dark_hours":5.4,"moon_illumination":57,"moon_separation":53.7,"score":null,"score_astronomy":29,"score_weather":null,"transit_alt":71.1,"transit_local":"08:30","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":1.92,"best_label":"good","best_window":"03:25\u201305:20","dark_hours":7.88,"date":"2040-04-04","moon_free_dark_hours":6.35,"moon_illumination":46,"moon_separation":48.8,"score":null,"score_astronomy":35,"score_weather":null,"transit_alt":71.1,"transit_local":"08:25","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":2.0,"best_label":"good","best_window":"03:20\u201305:20","dark_hours":7.83,"date":"2040-04-05","moon_free_dark_hours":7.12,"moon_illumination":35,"moon_separation":46.8,"score":null,"score_astronomy":45,"score_weather":null,"transit_alt":71.1,"transit_local":"08:25","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":2.0,"best_label":"good","best_window":"03:20\u201305:20","dark_hours":7.77,"date":"2040-04-06","moon_free_dark_hours":7.75,"moon_illumination":24,"moon_separation":47.9,"score":null,"score_astronomy":50,"score_weather":null,"transit_alt":71.1,"transit_local":"08:20","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":2.0,"best_label":"good","best_window":"03:15\u201305:15","dark_hours":7.72,"date":"2040-04-07","moon_free_dark_hours":7.7,"moon_illumination":16,"moon_separation":52.0,"score":null,"score_astronomy":52,"score_weather":null,"transit_alt":71.1,"transit_local":"08:15","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":2.08,"best_label":"good","best_window":"03:10\u201305:15","dark_hours":7.66,"date":"2040-04-08","moon_free_dark_hours":7.65,"moon_illumination":8,"moon_separation":58.3,"score":null,"score_astronomy":53,"score_weather":null,"transit_alt":71.1,"transit_local":"08:10","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":2.17,"best_label":"good","best_window":"03:05\u201305:15","dark_hours":7.6,"date":"2040-04-09","moon_free_dark_hours":7.6,"moon_illumination":3,"moon_separation":66.0,"score":null,"score_astronomy":54,"score_weather":null,"transit_alt":71.1,"transit_local":"08:05","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":2.17,"best_label":"good","best_window":"03:00\u201305:10","dark_hours":7.55,"date":"2040-04-10","moon_free_dark_hours":7.53,"moon_illumination":1,"moon_separation":74.5,"score":null,"score_astronomy":54,"score_weather":null,"transit_alt":71.1,"transit_local":"08:05","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":2.17,"best_label":"good","best_window":"03:00\u201305:10","dark_hours":7.49,"date":"2040-04-11","moon_free_dark_hours":7.48,"moon_illumination":0,"moon_separation":83.3,"score":null,"score_astronomy":56,"score_weather":null,"transit_alt":71.1,"transit_local":"08:00","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":2.17,"best_label":"good","best_window":"02:55\u201305:05","dark_hours":7.43,"date":"2040-04-12","moon_free_dark_hours":7.42,"moon_illumination":2,"moon_separation":92.2,"score":null,"score_astronomy":57,"score_weather":null,"transit_alt":71.1,"transit_local":"07:55","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":2.25,"best_label":"good","best_window":"02:50\u201305:05","dark_hours":7.37,"date":"2040-04-13","moon_free_dark_hours":7.02,"moon_illumination":6,"moon_separation":100.8,"score":null,"score_astronomy":57,"score_weather":null,"transit_alt":71.1,"transit_local":"07:50","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":2.33,"best_label":"good","best_window":"02:45\u201305:05","dark_hours":7.32,"date":"2040-04-14","moon_free_dark_hours":5.9,"moon_illumination":11,"moon_separation":108.9,"score":null,"score_astronomy":59,"score_weather":null,"transit_alt":71.1,"transit_local":"07:50","verdict":"unknown","weather_source":"none","weekday":"Sat"}],"note":"score_astronomy for every night; score_weather/score only where a forecast (next 4 days) or ERA5 history exists \u2014 null otherwise","start":"2040-03-16","target":{"dec":22.71085365,"name":"HD 189733","ra":300.18213726,"simbad_url":"https://simbad.cds.unistra.fr/simbad/sim-id?Ident=HD%20189733","source":"sesame","spectral_type":"K2V","type":"BY*","type_text":"BY Draconis variable \u2014 a spotted, rotating star","vmag":7.648}}