Rozhen Observation Calendar

Which nights are best for a target over the coming weeks. The astronomy mark (darkness × altitude × Moon) is computed for every night; the weather and the overall mark exist only where Open-Meteo has a forecast (the next four days) or ERA5 history (past nights) — the rest is honestly blank.

Best nights for V1057 Cyg: 05-30 (100), 05-31 (100), 06-01 (100), 06-02 (100), 06-03 (100) — by astronomy; check the weather when the night is within four days.

2044-05-30astronomy score per night — click a bar for that night2044-06-28

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2044-05-30 Mon	100	—	unknown	23:30–03:45 (good, 4.25 h)	87.3° 05:45	4.85	20%	112.5°
2044-05-31 Tue	100	—	unknown	23:30–03:45 (good, 4.25 h)	87.3° 05:40	4.81	30%	117.6°
2044-06-01 Wed	100	—	unknown	23:25–03:45 (good, 4.33 h)	87.2° 05:35	4.77	41%	121.0°
2044-06-02 Thu	100	—	unknown	23:25–03:45 (good, 4.33 h)	87.2° 05:35	4.74	52%	122.3°
2044-06-03 Fri	100	—	unknown	23:20–03:45 (good, 4.42 h)	87.3° 05:30	4.7	62%	121.7°
2044-06-04 Sat	100	—	unknown	23:20–03:40 (good, 4.33 h)	87.3° 05:25	4.67	72%	119.4°
2044-06-05 Sun	100	—	unknown	23:20–03:40 (good, 4.33 h)	87.3° 05:20	4.64	80%	115.6°
2044-06-06 Mon	100	—	unknown	23:20–03:40 (good, 4.33 h)	87.2° 05:15	4.62	88%	110.7°
2044-06-07 Tue	87	—	unknown	23:20–03:40 (good, 4.33 h)	87.2° 05:15	4.59	93%	105.2°
2044-06-08 Wed	83	—	unknown	23:20–03:40 (good, 4.33 h)	87.3° 05:10	4.56	97%	99.1°
2044-06-09 Thu	76	—	unknown	23:20–03:40 (good, 4.33 h)	87.3° 05:05	4.54	99%	92.8°
2044-06-10 Fri	70	—	unknown	23:20–03:40 (good, 4.33 h)	87.3° 05:00	4.52	100%	86.5°
2044-06-11 Sat	65	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:55	4.5	98%	80.2°
2044-06-12 Sun	63	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:55	4.48	95%	74.3°
2044-06-13 Mon	78	—	unknown	23:10–03:40 (good, 4.5 h)	87.3° 04:50	4.47	90%	68.9°
2044-06-14 Tue	83	—	unknown	23:10–03:40 (good, 4.5 h)	87.3° 04:45	4.46	84%	64.2°
2044-06-15 Wed	89	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:40	4.45	76%	60.6°
2044-06-16 Thu	93	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:40	4.44	68%	58.3°
2044-06-17 Fri	95	—	unknown	23:10–03:40 (good, 4.5 h)	87.3° 04:35	4.43	58%	57.5°
2044-06-18 Sat	98	—	unknown	23:10–03:40 (good, 4.5 h)	87.3° 04:30	4.42	48%	58.6°
2044-06-19 Sun	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:25	4.42	37%	61.4°
2044-06-20 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:20	4.42	27%	65.9°
2044-06-21 Tue	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:20	4.42	17%	71.9°
2044-06-22 Wed	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:15	4.43	9%	79.1°
2044-06-23 Thu	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:10	4.43	4%	86.9°
2044-06-24 Fri	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:05	4.44	1%	95.1°
2044-06-25 Sat	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:00	4.45	0%	103.0°
2044-06-26 Sun	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:00	4.46	4%	110.2°
2044-06-27 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 03:55	4.48	9%	116.1°
2044-06-28 Tue	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.3° 03:50	4.49	17%	120.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2044-05-30&days=30"
curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&days=30&format=csv" -o m31-calendar.csv

One row per night: score_astronomy always, score_weather / score only where a forecast or history exists (null otherwise, with weather_source saying which), best window, dark hours, Moon illumination and separation, transit. 7–60 nights. Errors: 400 with invalid_date or target_unresolved. Results are cached for six hours; calculation version 2026-10-10.1.