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: 10-16 (100), 10-17 (100), 10-18 (100), 10-19 (100), 10-20 (100) — by astronomy; check the weather when the night is within four days.

2034-10-16astronomy score per night — click a bar for that night2034-11-14

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-10-16 Mon	100	—	unknown	20:15–06:05 (good, 9.83 h)	89.7° 00:25	9.87	18%	121.8°
2034-10-17 Tue	100	—	unknown	20:10–06:05 (good, 9.92 h)	89.8° 00:20	9.91	26%	113.0°
2034-10-18 Wed	100	—	unknown	20:10–06:05 (good, 9.92 h)	89.7° 00:15	9.95	35%	103.7°
2034-10-19 Thu	100	—	unknown	20:10–06:10 (good, 10.0 h)	89.6° 00:10	9.99	44%	94.0°
2034-10-20 Fri	100	—	unknown	20:05–06:10 (good, 10.08 h)	89.6° 00:10	10.04	54%	84.0°
2034-10-21 Sat	100	—	unknown	20:05–06:10 (good, 10.08 h)	89.7° 00:05	10.08	64%	73.9°
2034-10-22 Sun	100	—	unknown	20:05–06:10 (good, 10.08 h)	89.8° 00:00	10.12	74%	63.7°
2034-10-23 Mon	92	—	unknown	00:20–06:05 (good, 5.75 h)	89.7° 23:55	10.16	83%	53.9°
2034-10-24 Tue	83	—	unknown	04:55–06:00 (good, 1.08 h)	89.5° 23:50	10.2	90%	45.2°
2034-10-25 Wed	54	—	unknown	20:00–06:15 (marginal, 10.25 h)	89.6° 23:50	10.24	96%	38.6°
2034-10-26 Thu	44	—	unknown	20:00–06:00 (marginal, 10.0 h)	89.7° 23:45	10.28	99%	36.1°
2034-10-27 Fri	49	—	unknown	20:00–05:40 (marginal, 9.67 h)	89.7° 23:40	10.32	100%	38.8°
2034-10-28 Sat	59	—	unknown	19:55–04:30 (marginal, 9.58 h)	89.6° 23:35	10.35	97%	45.9°
2034-10-29 Sun	96	—	unknown	18:55–21:40 (good, 2.75 h)	89.5° 22:35	10.39	91%	55.6°
2034-10-30 Mon	100	—	unknown	18:55–01:05 (good, 6.17 h)	89.7° 22:30	10.43	84%	66.5°
2034-10-31 Tue	100	—	unknown	18:55–02:55 (good, 8.0 h)	89.8° 22:25	10.47	74%	77.9°
2034-11-01 Wed	100	—	unknown	18:50–04:05 (good, 9.25 h)	89.7° 22:20	10.5	63%	89.3°
2034-11-02 Thu	100	—	unknown	18:50–04:10 (good, 9.33 h)	89.6° 22:15	10.54	52%	100.3°
2034-11-03 Fri	100	—	unknown	18:50–04:15 (good, 9.42 h)	89.6° 22:15	10.58	42%	110.8°
2034-11-04 Sat	100	—	unknown	18:50–04:15 (good, 9.42 h)	89.7° 22:10	10.61	32%	120.6°
2034-11-05 Sun	100	—	unknown	18:50–04:10 (good, 9.33 h)	89.8° 22:05	10.64	23%	129.3°
2034-11-06 Mon	100	—	unknown	18:45–04:10 (good, 9.42 h)	89.7° 22:00	10.68	15%	136.6°
2034-11-07 Tue	100	—	unknown	18:45–04:05 (good, 9.33 h)	89.5° 21:55	10.71	9%	141.7°
2034-11-08 Wed	100	—	unknown	18:45–04:00 (good, 9.25 h)	89.6° 21:55	10.75	4%	143.8°
2034-11-09 Thu	100	—	unknown	18:45–04:00 (good, 9.25 h)	89.7° 21:50	10.78	1%	142.5°
2034-11-10 Fri	100	—	unknown	18:45–03:55 (good, 9.17 h)	89.7° 21:45	10.81	0%	138.3°
2034-11-11 Sat	100	—	unknown	18:45–03:50 (good, 9.08 h)	89.6° 21:40	10.84	1%	131.9°
2034-11-12 Sun	100	—	unknown	18:40–03:45 (good, 9.08 h)	89.5° 21:40	10.87	3%	124.1°
2034-11-13 Mon	100	—	unknown	18:40–03:45 (good, 9.08 h)	89.7° 21:35	10.9	7%	115.5°
2034-11-14 Tue	100	—	unknown	18:40–03:40 (good, 9.0 h)	89.8° 21:30	10.93	13%	106.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-10-16&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.