{"calculation_version":"2026-10-10.1","days":30,"nights":[{"best_hours":0.17,"best_label":"marginal","best_window":"18:45\u201318:55","dark_hours":11.4,"date":"2039-01-05","moon_free_dark_hours":2.23,"moon_illumination":82,"moon_separation":104.0,"score":null,"score_astronomy":2,"score_weather":null,"transit_alt":71.1,"transit_local":"13:25","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.08,"best_label":"marginal","best_window":"18:50\u201318:55","dark_hours":11.39,"date":"2039-01-06","moon_free_dark_hours":1.23,"moon_illumination":88,"moon_separation":111.9,"score":null,"score_astronomy":2,"score_weather":null,"transit_alt":71.1,"transit_local":"13:20","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.38,"date":"2039-01-07","moon_free_dark_hours":0.25,"moon_illumination":94,"moon_separation":119.3,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"13:15","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.36,"date":"2039-01-08","moon_free_dark_hours":0.0,"moon_illumination":98,"moon_separation":125.8,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"13:10","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.34,"date":"2039-01-09","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":131.0,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"13:10","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.33,"date":"2039-01-10","moon_free_dark_hours":0.0,"moon_illumination":100,"moon_separation":134.1,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"13:05","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.31,"date":"2039-01-11","moon_free_dark_hours":0.0,"moon_illumination":98,"moon_separation":134.6,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"13:00","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.29,"date":"2039-01-12","moon_free_dark_hours":0.43,"moon_illumination":94,"moon_separation":132.3,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"12:55","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.27,"date":"2039-01-13","moon_free_dark_hours":1.53,"moon_illumination":88,"moon_separation":127.5,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:50","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.25,"date":"2039-01-14","moon_free_dark_hours":2.65,"moon_illumination":80,"moon_separation":120.7,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:50","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.23,"date":"2039-01-15","moon_free_dark_hours":3.78,"moon_illumination":70,"moon_separation":112.4,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:45","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.21,"date":"2039-01-16","moon_free_dark_hours":4.93,"moon_illumination":59,"moon_separation":103.3,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:40","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.18,"date":"2039-01-17","moon_free_dark_hours":6.08,"moon_illumination":48,"moon_separation":93.6,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:35","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.16,"date":"2039-01-18","moon_free_dark_hours":7.28,"moon_illumination":37,"moon_separation":83.6,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:35","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.14,"date":"2039-01-19","moon_free_dark_hours":8.5,"moon_illumination":26,"moon_separation":73.8,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:30","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.11,"date":"2039-01-20","moon_free_dark_hours":9.72,"moon_illumination":17,"moon_separation":64.4,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:25","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.09,"date":"2039-01-21","moon_free_dark_hours":10.88,"moon_illumination":9,"moon_separation":56.2,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:20","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.06,"date":"2039-01-22","moon_free_dark_hours":11.05,"moon_illumination":4,"moon_separation":49.7,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:15","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.03,"date":"2039-01-23","moon_free_dark_hours":11.02,"moon_illumination":1,"moon_separation":45.9,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:15","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":11.01,"date":"2039-01-24","moon_free_dark_hours":11.0,"moon_illumination":0,"moon_separation":45.4,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:10","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":10.98,"date":"2039-01-25","moon_free_dark_hours":10.97,"moon_illumination":2,"moon_separation":48.2,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:05","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":10.95,"date":"2039-01-26","moon_free_dark_hours":10.52,"moon_illumination":7,"moon_separation":53.4,"score":null,"score_astronomy":0,"score_weather":null,"transit_alt":71.1,"transit_local":"12:00","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":10.92,"date":"2039-01-27","moon_free_dark_hours":9.4,"moon_illumination":13,"moon_separation":60.2,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"11:55","verdict":"unknown","weather_source":"none","weekday":"Thu"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":10.89,"date":"2039-01-28","moon_free_dark_hours":8.32,"moon_illumination":20,"moon_separation":68.0,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"11:50","verdict":"unknown","weather_source":"none","weekday":"Fri"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":10.86,"date":"2039-01-29","moon_free_dark_hours":7.27,"moon_illumination":29,"moon_separation":76.2,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"11:45","verdict":"unknown","weather_source":"none","weekday":"Sat"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":10.83,"date":"2039-01-30","moon_free_dark_hours":6.25,"moon_illumination":38,"moon_separation":84.6,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"11:40","verdict":"unknown","weather_source":"none","weekday":"Sun"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":10.79,"date":"2039-01-31","moon_free_dark_hours":5.25,"moon_illumination":48,"moon_separation":93.0,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"11:40","verdict":"unknown","weather_source":"none","weekday":"Mon"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":10.76,"date":"2039-02-01","moon_free_dark_hours":4.25,"moon_illumination":57,"moon_separation":101.2,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"11:35","verdict":"unknown","weather_source":"none","weekday":"Tue"},{"best_hours":0.0,"best_label":null,"best_window":null,"dark_hours":10.73,"date":"2039-02-02","moon_free_dark_hours":3.23,"moon_illumination":66,"moon_separation":109.2,"score":null,"score_astronomy":1,"score_weather":null,"transit_alt":71.1,"transit_local":"11:30","verdict":"unknown","weather_source":"none","weekday":"Wed"},{"best_hours":0.08,"best_label":"marginal","best_window":"05:55\u201306:00","dark_hours":10.7,"date":"2039-02-03","moon_free_dark_hours":2.23,"moon_illumination":75,"moon_separation":116.8,"score":null,"score_astronomy":2,"score_weather":null,"transit_alt":71.1,"transit_local":"11:25","verdict":"unknown","weather_source":"none","weekday":"Thu"}],"note":"score_astronomy for every night; score_weather/score only where a forecast (next 4 days) or ERA5 history exists \u2014 null otherwise","start":"2039-01-05","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}}