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 Triangulum Pinwheel: 12-05 (100), 12-06 (100), 12-07 (100), 12-08 (100), 12-18 (100) — by astronomy; check the weather when the night is within four days.

2043-12-05astronomy score per night — click a bar for that night2044-01-03

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-12-05 Sat	100	—	unknown	18:35–02:30 (good, 7.92 h)	79.2° 21:00	11.39	16%	93.6°
2043-12-06 Sun	100	—	unknown	18:35–02:30 (good, 7.92 h)	79.2° 20:55	11.41	24%	81.9°
2043-12-07 Mon	100	—	unknown	18:35–02:25 (good, 7.83 h)	79.2° 20:50	11.42	33%	70.0°
2043-12-08 Tue	100	—	unknown	18:35–02:20 (good, 7.75 h)	79.2° 20:50	11.43	42%	58.0°
2043-12-09 Wed	90	—	unknown	18:35–02:15 (good, 7.67 h)	79.2° 20:45	11.44	53%	45.8°
2043-12-10 Thu	81	—	unknown	21:35–02:10 (good, 4.58 h)	79.2° 20:40	11.45	64%	33.7°
2043-12-11 Fri	52	—	unknown	18:35–02:35 (marginal, 8.0 h)	79.2° 20:35	11.46	74%	22.7°
2043-12-12 Sat	34	—	unknown	18:35–02:15 (marginal, 7.67 h)	79.2° 20:30	11.47	83%	16.3°
2043-12-13 Sun	24	—	unknown	22:25–01:45 (marginal, 3.33 h)	79.2° 20:30	11.48	91%	20.8°
2043-12-14 Mon	22	—	unknown	18:35–20:25 (marginal, 1.83 h)	79.2° 20:25	11.49	97%	32.2°
2043-12-15 Tue	36	—	unknown	18:35–23:45 (marginal, 5.17 h)	79.2° 20:20	11.49	100%	45.9°
2043-12-16 Wed	58	—	unknown	18:35–19:10 (good, 0.58 h)	79.2° 20:15	11.5	99%	60.2°
2043-12-17 Thu	75	—	unknown	18:35–22:35 (good, 4.0 h)	79.2° 20:10	11.5	96%	74.5°
2043-12-18 Fri	100	—	unknown	18:35–00:20 (good, 5.75 h)	79.2° 20:10	11.5	90%	88.7°
2043-12-19 Sat	100	—	unknown	18:35–01:15 (good, 6.67 h)	79.2° 20:05	11.51	82%	102.5°
2043-12-20 Sun	100	—	unknown	18:35–01:20 (good, 6.75 h)	79.2° 20:00	11.51	73%	115.8°
2043-12-21 Mon	100	—	unknown	18:35–01:25 (good, 6.83 h)	79.2° 19:55	11.51	63%	128.4°
2043-12-22 Tue	100	—	unknown	18:35–01:20 (good, 6.75 h)	79.2° 19:55	11.51	53%	140.3°
2043-12-23 Wed	100	—	unknown	18:40–01:20 (good, 6.67 h)	79.2° 19:50	11.51	43%	151.2°
2043-12-24 Thu	100	—	unknown	18:40–01:15 (good, 6.58 h)	79.2° 19:45	11.5	33%	160.0°
2043-12-25 Fri	100	—	unknown	18:40–01:15 (good, 6.58 h)	79.2° 19:40	11.5	25%	163.8°
2043-12-26 Sat	100	—	unknown	18:40–01:10 (good, 6.5 h)	79.2° 19:35	11.5	17%	160.0°
2043-12-27 Sun	100	—	unknown	18:40–01:05 (good, 6.42 h)	79.2° 19:35	11.49	11%	151.5°
2043-12-28 Mon	100	—	unknown	18:40–01:00 (good, 6.33 h)	79.2° 19:30	11.49	6%	141.3°
2043-12-29 Tue	100	—	unknown	18:40–01:00 (good, 6.33 h)	79.2° 19:25	11.48	2%	130.5°
2043-12-30 Wed	100	—	unknown	18:40–00:55 (good, 6.25 h)	79.2° 19:20	11.47	0%	119.3°
2043-12-31 Thu	100	—	unknown	18:45–00:50 (good, 6.08 h)	79.2° 19:15	11.46	0%	107.9°
2044-01-01 Fri	100	—	unknown	18:45–00:45 (good, 6.0 h)	79.2° 19:15	11.45	2%	96.3°
2044-01-02 Sat	100	—	unknown	18:45–00:40 (good, 5.92 h)	79.2° 19:10	11.44	6%	84.5°
2044-01-03 Sun	100	—	unknown	18:45–00:40 (good, 5.92 h)	79.2° 19:05	11.43	11%	72.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-12-05&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.