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 Andromeda Galaxy: 10-12 (100), 10-13 (100), 10-14 (100), 10-15 (100), 10-16 (100) — by astronomy; check the weather when the night is within four days.

2044-10-03astronomy score per night — click a bar for that night2044-11-01

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2044-10-03 Mon	97	—	unknown	00:35–05:50 (good, 5.25 h)	89.6° 01:15	9.31	90%	60.7°
2044-10-04 Tue	89	—	unknown	03:50–05:55 (good, 2.08 h)	89.8° 01:10	9.35	95%	50.5°
2044-10-05 Wed	51	—	unknown	20:30–05:55 (marginal, 9.42 h)	89.8° 01:05	9.4	99%	41.2°
2044-10-06 Thu	37	—	unknown	01:50–05:55 (marginal, 4.08 h)	89.7° 01:00	9.45	100%	33.6°
2044-10-07 Fri	35	—	unknown	20:25–23:40 (marginal, 3.25 h)	89.5° 00:55	9.49	99%	29.7°
2044-10-08 Sat	42	—	unknown	20:25–00:55 (marginal, 4.5 h)	89.7° 00:55	9.54	96%	31.2°
2044-10-09 Sun	56	—	unknown	20:25–06:00 (marginal, 9.58 h)	89.8° 00:50	9.58	90%	37.7°
2044-10-10 Mon	89	—	unknown	20:20–23:20 (good, 3.0 h)	89.8° 00:45	9.63	82%	47.3°
2044-10-11 Tue	96	—	unknown	20:20–03:15 (good, 6.92 h)	89.6° 00:40	9.67	72%	58.4°
2044-10-12 Wed	100	—	unknown	20:20–05:20 (good, 9.0 h)	89.6° 00:40	9.72	61%	70.2°
2044-10-13 Thu	100	—	unknown	20:15–06:05 (good, 9.83 h)	89.7° 00:35	9.76	50%	82.4°
2044-10-14 Fri	100	—	unknown	20:15–06:05 (good, 9.83 h)	89.8° 00:30	9.81	39%	94.7°
2044-10-15 Sat	100	—	unknown	20:15–06:05 (good, 9.83 h)	89.7° 00:25	9.85	28%	106.8°
2044-10-16 Sun	100	—	unknown	20:10–06:05 (good, 9.92 h)	89.6° 00:20	9.89	18%	118.6°
2044-10-17 Mon	100	—	unknown	20:10–06:05 (good, 9.92 h)	89.6° 00:20	9.93	11%	129.7°
2044-10-18 Tue	100	—	unknown	20:10–06:10 (good, 10.0 h)	89.8° 00:15	9.98	5%	139.5°
2044-10-19 Wed	100	—	unknown	20:10–06:10 (good, 10.0 h)	89.8° 00:10	10.02	1%	146.9°
2044-10-20 Thu	100	—	unknown	20:05–06:10 (good, 10.08 h)	89.7° 00:05	10.06	0%	150.4°
2044-10-21 Fri	100	—	unknown	20:05–06:10 (good, 10.08 h)	89.5° 00:00	10.1	1%	148.8°
2044-10-22 Sat	100	—	unknown	20:05–06:05 (good, 10.0 h)	89.7° 00:00	10.14	4%	143.1°
2044-10-23 Sun	100	—	unknown	20:05–06:05 (good, 10.0 h)	89.8° 23:55	10.18	9%	135.0°
2044-10-24 Mon	100	—	unknown	20:00–06:00 (good, 10.0 h)	89.8° 23:50	10.22	15%	125.7°
2044-10-25 Tue	100	—	unknown	20:00–05:55 (good, 9.92 h)	89.6° 23:45	10.26	23%	115.8°
2044-10-26 Wed	100	—	unknown	20:00–05:50 (good, 9.83 h)	89.5° 23:45	10.3	31%	105.7°
2044-10-27 Thu	100	—	unknown	19:55–05:50 (good, 9.92 h)	89.7° 23:40	10.34	40%	95.5°
2044-10-28 Fri	100	—	unknown	19:55–05:45 (good, 9.83 h)	89.8° 23:35	10.38	49%	85.2°
2044-10-29 Sat	100	—	unknown	19:55–04:40 (good, 9.75 h)	89.7° 23:30	10.41	59%	74.8°
2044-10-30 Sun	100	—	unknown	18:55–04:35 (good, 9.67 h)	89.6° 22:25	10.45	68%	64.5°
2044-10-31 Mon	92	—	unknown	19:30–04:30 (good, 9.0 h)	89.6° 22:25	10.49	77%	54.3°
2044-11-01 Tue	84	—	unknown	03:15–04:30 (good, 1.25 h)	89.8° 22:20	10.52	85%	44.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2044-10-03&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.