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: 12-08 (100), 12-09 (100), 12-10 (99), 12-11 (98), 12-07 (96) — by astronomy; check the weather when the night is within four days.

2044-11-30astronomy score per night — click a bar for that night2044-12-29

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2044-11-30 Wed	41	—	unknown	18:00–23:20 (marginal, 5.33 h)	87.3° 16:40	11.32	80%	61.3°
2044-12-01 Thu	38	—	unknown	18:35–23:10 (marginal, 4.58 h)	87.2° 16:35	11.34	88%	66.0°
2044-12-02 Fri	40	—	unknown	18:35–19:00 (good, 0.42 h)	87.2° 16:35	11.36	94%	72.3°
2044-12-03 Sat	45	—	unknown	18:35–19:45 (good, 1.17 h)	87.3° 16:30	11.37	98%	79.6°
2044-12-04 Sun	53	—	unknown	18:35–20:35 (good, 2.0 h)	87.3° 16:25	11.39	100%	87.5°
2044-12-05 Mon	64	—	unknown	18:35–21:35 (good, 3.0 h)	87.2° 16:20	11.4	98%	95.7°
2044-12-06 Tue	76	—	unknown	18:35–22:10 (good, 3.58 h)	87.2° 16:15	11.42	94%	103.6°
2044-12-07 Wed	96	—	unknown	18:35–22:15 (good, 3.67 h)	87.2° 16:15	11.43	88%	110.8°
2044-12-08 Thu	100	—	unknown	18:35–22:20 (good, 3.75 h)	87.3° 16:10	11.44	79%	116.8°
2044-12-09 Fri	100	—	unknown	18:35–22:20 (good, 3.75 h)	87.3° 16:05	11.45	68%	120.9°
2044-12-10 Sat	99	—	unknown	18:35–22:20 (good, 3.75 h)	87.2° 16:00	11.46	58%	123.1°
2044-12-11 Sun	98	—	unknown	18:35–22:20 (good, 3.75 h)	87.2° 16:00	11.47	47%	123.0°
2044-12-12 Mon	96	—	unknown	18:35–22:15 (good, 3.67 h)	87.3° 15:55	11.48	36%	120.9°
2044-12-13 Tue	95	—	unknown	18:35–22:10 (good, 3.58 h)	87.3° 15:50	11.48	26%	117.2°
2044-12-14 Wed	92	—	unknown	18:35–22:05 (good, 3.5 h)	87.3° 15:45	11.49	18%	112.2°
2044-12-15 Thu	90	—	unknown	18:35–22:00 (good, 3.42 h)	87.2° 15:40	11.49	11%	106.4°
2044-12-16 Fri	89	—	unknown	18:35–22:00 (good, 3.42 h)	87.2° 15:40	11.5	6%	100.1°
2044-12-17 Sat	86	—	unknown	18:35–21:55 (good, 3.33 h)	87.3° 15:35	11.5	2%	93.5°
2044-12-18 Sun	84	—	unknown	18:35–21:50 (good, 3.25 h)	87.3° 15:30	11.51	0%	86.9°
2044-12-19 Mon	82	—	unknown	18:35–21:45 (good, 3.17 h)	87.2° 15:25	11.51	0%	80.4°
2044-12-20 Tue	79	—	unknown	18:35–21:40 (good, 3.08 h)	87.2° 15:20	11.51	2%	74.3°
2044-12-21 Wed	78	—	unknown	18:35–21:40 (good, 3.08 h)	87.2° 15:20	11.51	6%	68.7°
2044-12-22 Thu	72	—	unknown	18:35–21:35 (good, 3.0 h)	87.3° 15:15	11.51	11%	63.9°
2044-12-23 Fri	65	—	unknown	18:40–21:30 (good, 2.83 h)	87.3° 15:10	11.5	17%	60.1°
2044-12-24 Sat	57	—	unknown	18:40–21:20 (good, 2.67 h)	87.2° 15:05	11.5	25%	57.5°
2044-12-25 Sun	49	—	unknown	18:40–21:05 (good, 2.42 h)	87.2° 15:05	11.5	34%	56.6°
2044-12-26 Mon	41	—	unknown	18:40–20:55 (good, 2.25 h)	87.3° 15:00	11.49	44%	57.3°
2044-12-27 Tue	34	—	unknown	18:40–20:20 (good, 1.67 h)	87.3° 14:55	11.49	54%	59.7°
2044-12-28 Wed	28	—	unknown	18:40–19:05 (good, 0.42 h)	87.3° 14:50	11.48	64%	63.8°
2044-12-29 Thu	25	—	unknown	18:40–21:30 (marginal, 2.83 h)	87.2° 14:45	11.47	74%	69.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2044-11-30&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.