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: 11-13 (100), 11-14 (100), 11-15 (100), 11-16 (100), 11-17 (100) — by astronomy; check the weather when the night is within four days.

2036-11-13astronomy score per night — click a bar for that night2036-12-12

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-11-13 Thu	100	—	unknown	18:40–03:40 (good, 9.0 h)	89.6° 21:30	10.92	20%	134.3°
2036-11-14 Fri	100	—	unknown	18:40–03:35 (good, 8.92 h)	89.5° 21:30	10.95	12%	139.9°
2036-11-15 Sat	100	—	unknown	18:40–03:35 (good, 8.92 h)	89.7° 21:25	10.98	5%	141.8°
2036-11-16 Sun	100	—	unknown	18:40–03:30 (good, 8.83 h)	89.8° 21:20	11.0	2%	139.5°
2036-11-17 Mon	100	—	unknown	18:40–03:25 (good, 8.75 h)	89.7° 21:15	11.03	0%	133.9°
2036-11-18 Tue	100	—	unknown	18:35–03:20 (good, 8.75 h)	89.5° 21:10	11.06	1%	126.2°
2036-11-19 Wed	100	—	unknown	18:35–03:15 (good, 8.67 h)	89.6° 21:10	11.08	4%	117.3°
2036-11-20 Thu	100	—	unknown	18:35–03:15 (good, 8.67 h)	89.7° 21:05	11.11	9%	108.0°
2036-11-21 Fri	100	—	unknown	18:35–03:10 (good, 8.58 h)	89.8° 21:00	11.13	15%	98.4°
2036-11-22 Sat	100	—	unknown	18:35–03:05 (good, 8.5 h)	89.7° 20:55	11.16	23%	88.9°
2036-11-23 Sun	100	—	unknown	18:35–03:00 (good, 8.42 h)	89.5° 20:55	11.18	32%	79.5°
2036-11-24 Mon	100	—	unknown	18:35–02:55 (good, 8.33 h)	89.7° 20:50	11.2	40%	70.4°
2036-11-25 Tue	98	—	unknown	18:35–02:55 (good, 8.33 h)	89.8° 20:45	11.23	50%	61.7°
2036-11-26 Wed	91	—	unknown	18:35–02:50 (good, 8.25 h)	89.7° 20:40	11.25	59%	53.7°
2036-11-27 Thu	84	—	unknown	18:35–02:45 (good, 8.17 h)	89.6° 20:35	11.27	68%	46.6°
2036-11-28 Fri	63	—	unknown	02:35–02:40 (good, 0.08 h)	89.5° 20:35	11.29	77%	41.3°
2036-11-29 Sat	49	—	unknown	18:35–03:00 (marginal, 8.42 h)	89.7° 20:30	11.31	85%	38.5°
2036-11-30 Sun	42	—	unknown	18:35–02:40 (marginal, 8.08 h)	89.8° 20:25	11.32	92%	39.1°
2036-12-01 Mon	42	—	unknown	18:35–02:20 (marginal, 7.75 h)	89.7° 20:20	11.34	96%	43.3°
2036-12-02 Tue	49	—	unknown	18:35–02:10 (marginal, 7.58 h)	89.5° 20:15	11.36	99%	50.4°
2036-12-03 Wed	63	—	unknown	18:35–19:15 (good, 0.67 h)	89.6° 20:15	11.37	100%	59.4°
2036-12-04 Thu	72	—	unknown	18:35–21:30 (good, 2.92 h)	89.7° 20:10	11.39	98%	69.7°
2036-12-05 Fri	100	—	unknown	18:35–23:45 (good, 5.17 h)	89.8° 20:05	11.4	93%	80.7°
2036-12-06 Sat	100	—	unknown	18:35–01:10 (good, 6.58 h)	89.7° 20:00	11.41	86%	91.9°
2036-12-07 Sun	100	—	unknown	18:35–01:45 (good, 7.17 h)	89.5° 19:55	11.43	77%	103.2°
2036-12-08 Mon	100	—	unknown	18:35–01:50 (good, 7.25 h)	89.6° 19:55	11.44	66%	114.0°
2036-12-09 Tue	100	—	unknown	18:35–01:50 (good, 7.25 h)	89.8° 19:50	11.45	55%	123.9°
2036-12-10 Wed	100	—	unknown	18:35–01:50 (good, 7.25 h)	89.7° 19:45	11.46	44%	132.5°
2036-12-11 Thu	100	—	unknown	18:35–01:50 (good, 7.25 h)	89.6° 19:40	11.47	33%	138.7°
2036-12-12 Fri	100	—	unknown	18:35–01:45 (good, 7.17 h)	89.5° 19:40	11.48	23%	141.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-11-13&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.