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: 09-29 (100), 09-30 (100), 10-01 (100), 10-02 (100), 10-03 (100) — by astronomy; check the weather when the night is within four days.

2033-09-29astronomy score per night — click a bar for that night2033-10-28

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-09-29 Thu	100	—	unknown	20:40–05:45 (good, 9.08 h)	89.8° 01:30	9.1	32%	120.2°
2033-09-30 Fri	100	—	unknown	20:40–05:50 (good, 9.17 h)	89.7° 01:25	9.15	42%	110.6°
2033-10-01 Sat	100	—	unknown	20:35–05:50 (good, 9.25 h)	89.6° 01:20	9.19	52%	100.3°
2033-10-02 Sun	100	—	unknown	20:35–05:50 (good, 9.25 h)	89.5° 01:20	9.24	63%	89.5°
2033-10-03 Mon	100	—	unknown	20:35–05:50 (good, 9.25 h)	89.7° 01:15	9.29	73%	78.3°
2033-10-04 Tue	100	—	unknown	21:30–05:50 (good, 8.33 h)	89.8° 01:10	9.34	83%	67.0°
2033-10-05 Wed	94	—	unknown	02:00–05:55 (good, 3.92 h)	89.7° 01:05	9.38	91%	56.0°
2033-10-06 Thu	85	—	unknown	05:50–05:55 (good, 0.08 h)	89.5° 01:00	9.43	96%	45.9°
2033-10-07 Fri	46	—	unknown	20:25–05:55 (marginal, 9.5 h)	89.6° 01:00	9.48	100%	38.1°
2033-10-08 Sat	41	—	unknown	20:25–05:55 (marginal, 9.5 h)	89.7° 00:55	9.52	100%	34.6°
2033-10-09 Sun	51	—	unknown	20:25–06:00 (marginal, 9.58 h)	89.8° 00:50	9.57	97%	36.8°
2033-10-10 Mon	88	—	unknown	20:20–20:45 (good, 0.42 h)	89.6° 00:45	9.61	91%	43.6°
2033-10-11 Tue	94	—	unknown	20:20–00:10 (good, 3.83 h)	89.5° 00:40	9.66	83%	53.0°
2033-10-12 Wed	100	—	unknown	20:20–03:45 (good, 7.42 h)	89.6° 00:40	9.7	74%	63.5°
2033-10-13 Thu	100	—	unknown	20:15–05:30 (good, 9.25 h)	89.7° 00:35	9.75	63%	74.4°
2033-10-14 Fri	100	—	unknown	20:15–06:05 (good, 9.83 h)	89.7° 00:30	9.79	53%	85.2°
2033-10-15 Sat	100	—	unknown	20:15–06:05 (good, 9.83 h)	89.6° 00:25	9.83	43%	95.7°
2033-10-16 Sun	100	—	unknown	20:15–06:05 (good, 9.83 h)	89.5° 00:25	9.88	33%	105.9°
2033-10-17 Mon	100	—	unknown	20:10–06:05 (good, 9.92 h)	89.7° 00:20	9.92	24%	115.6°
2033-10-18 Tue	100	—	unknown	20:10–06:10 (good, 10.0 h)	89.8° 00:15	9.96	16%	124.7°
2033-10-19 Wed	100	—	unknown	20:10–06:10 (good, 10.0 h)	89.7° 00:10	10.0	10%	132.9°
2033-10-20 Thu	100	—	unknown	20:05–06:10 (good, 10.08 h)	89.5° 00:05	10.05	5%	139.5°
2033-10-21 Fri	100	—	unknown	20:05–06:10 (good, 10.08 h)	89.6° 00:05	10.09	2%	144.0°
2033-10-22 Sat	100	—	unknown	20:05–06:10 (good, 10.08 h)	89.7° 00:00	10.13	0%	145.4°
2033-10-23 Sun	100	—	unknown	20:05–06:05 (good, 10.0 h)	89.8° 23:55	10.17	0%	143.3°
2033-10-24 Mon	100	—	unknown	20:00–06:00 (good, 10.0 h)	89.6° 23:50	10.21	2%	138.2°
2033-10-25 Tue	100	—	unknown	20:00–05:55 (good, 9.92 h)	89.5° 23:45	10.25	6%	131.1°
2033-10-26 Wed	100	—	unknown	20:00–05:50 (good, 9.83 h)	89.6° 23:45	10.29	12%	122.5°
2033-10-27 Thu	100	—	unknown	20:00–05:50 (good, 9.83 h)	89.7° 23:40	10.33	19%	113.1°
2033-10-28 Fri	100	—	unknown	19:55–05:45 (good, 9.83 h)	89.7° 23:35	10.36	27%	103.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-09-29&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.