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: 11-17 (100), 11-18 (100), 11-19 (100), 11-20 (100), 11-21 (100) — by astronomy; check the weather when the night is within four days.

2035-11-10astronomy score per night — click a bar for that night2035-12-09

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-11-10 Sat	88	—	unknown	21:25–03:55 (good, 6.5 h)	89.6° 21:45	10.8	75%	50.7°
2035-11-11 Sun	81	—	unknown	03:05–03:50 (good, 0.75 h)	89.5° 21:45	10.83	84%	43.5°
2035-11-12 Mon	48	—	unknown	18:40–04:10 (marginal, 9.5 h)	89.7° 21:40	10.86	91%	38.7°
2035-11-13 Tue	44	—	unknown	18:40–03:50 (marginal, 9.17 h)	89.8° 21:35	10.89	96%	37.6°
2035-11-14 Wed	46	—	unknown	18:40–03:30 (marginal, 8.83 h)	89.7° 21:30	10.92	99%	40.8°
2035-11-15 Thu	59	—	unknown	18:40–03:20 (marginal, 8.67 h)	89.6° 21:25	10.95	100%	47.8°
2035-11-16 Fri	68	—	unknown	18:40–20:15 (good, 1.58 h)	89.6° 21:25	10.98	97%	57.3°
2035-11-17 Sat	100	—	unknown	18:40–22:55 (good, 4.25 h)	89.7° 21:20	11.01	92%	68.1°
2035-11-18 Sun	100	—	unknown	18:40–01:15 (good, 6.58 h)	89.8° 21:15	11.04	84%	79.5°
2035-11-19 Mon	100	—	unknown	18:35–02:45 (good, 8.17 h)	89.7° 21:10	11.06	75%	91.1°
2035-11-20 Tue	100	—	unknown	18:35–03:00 (good, 8.42 h)	89.5° 21:05	11.09	64%	102.4°
2035-11-21 Wed	100	—	unknown	18:35–03:05 (good, 8.5 h)	89.6° 21:05	11.11	53%	113.2°
2035-11-22 Thu	100	—	unknown	18:35–03:05 (good, 8.5 h)	89.7° 21:00	11.14	42%	123.1°
2035-11-23 Fri	100	—	unknown	18:35–03:00 (good, 8.42 h)	89.8° 20:55	11.16	32%	131.7°
2035-11-24 Sat	100	—	unknown	18:35–03:00 (good, 8.42 h)	89.6° 20:50	11.19	22%	138.2°
2035-11-25 Sun	100	—	unknown	18:35–02:55 (good, 8.33 h)	89.5° 20:50	11.21	15%	141.9°
2035-11-26 Mon	100	—	unknown	18:35–02:50 (good, 8.25 h)	89.7° 20:45	11.23	8%	142.1°
2035-11-27 Tue	100	—	unknown	18:35–02:50 (good, 8.25 h)	89.8° 20:40	11.25	4%	138.9°
2035-11-28 Wed	100	—	unknown	18:35–02:45 (good, 8.17 h)	89.7° 20:35	11.27	1%	133.1°
2035-11-29 Thu	100	—	unknown	18:35–02:40 (good, 8.08 h)	89.6° 20:30	11.29	0%	125.6°
2035-11-30 Fri	100	—	unknown	18:35–02:35 (good, 8.0 h)	89.5° 20:30	11.31	1%	117.2°
2035-12-01 Sat	100	—	unknown	18:35–02:35 (good, 8.0 h)	89.7° 20:25	11.33	4%	108.3°
2035-12-02 Sun	100	—	unknown	18:35–02:30 (good, 7.92 h)	89.8° 20:20	11.34	9%	99.0°
2035-12-03 Mon	100	—	unknown	18:35–02:25 (good, 7.83 h)	89.7° 20:15	11.36	15%	89.7°
2035-12-04 Tue	100	—	unknown	18:35–02:20 (good, 7.75 h)	89.5° 20:10	11.38	22%	80.4°
2035-12-05 Wed	100	—	unknown	18:35–02:15 (good, 7.67 h)	89.6° 20:10	11.39	30%	71.1°
2035-12-06 Thu	99	—	unknown	18:35–02:15 (good, 7.67 h)	89.7° 20:05	11.4	39%	62.2°
2035-12-07 Fri	92	—	unknown	18:35–02:10 (good, 7.58 h)	89.8° 20:00	11.42	49%	53.7°
2035-12-08 Sat	85	—	unknown	18:35–02:05 (good, 7.5 h)	89.6° 19:55	11.43	59%	46.2°
2035-12-09 Sun	65	—	unknown	22:05–00:00 (good, 1.92 h)	89.5° 19:55	11.44	69%	40.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-11-10&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.