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: 11-08 (100), 11-09 (100), 11-10 (100), 11-11 (100), 11-12 (100) — by astronomy; check the weather when the night is within four days.

2028-11-08astronomy score per night — click a bar for that night2028-12-07

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2028-11-08 Wed	100	—	unknown	18:45–03:40 (good, 8.92 h)	89.6° 21:50	10.76	61%	96.6°
2028-11-09 Thu	100	—	unknown	18:45–03:45 (good, 9.0 h)	89.5° 21:45	10.79	50%	108.6°
2028-11-10 Fri	100	—	unknown	18:45–03:45 (good, 9.0 h)	89.6° 21:45	10.82	38%	120.6°
2028-11-11 Sat	100	—	unknown	18:40–03:45 (good, 9.08 h)	89.7° 21:40	10.86	28%	132.1°
2028-11-12 Sun	100	—	unknown	18:40–03:45 (good, 9.08 h)	89.7° 21:35	10.89	18%	142.3°
2028-11-13 Mon	100	—	unknown	18:40–03:40 (good, 9.0 h)	89.6° 21:30	10.92	10%	149.7°
2028-11-14 Tue	100	—	unknown	18:40–03:35 (good, 8.92 h)	89.5° 21:30	10.95	4%	151.4°
2028-11-15 Wed	100	—	unknown	18:40–03:30 (good, 8.83 h)	89.6° 21:25	10.97	1%	146.7°
2028-11-16 Thu	100	—	unknown	18:40–03:30 (good, 8.83 h)	89.7° 21:20	11.0	0%	137.8°
2028-11-17 Fri	100	—	unknown	18:40–03:25 (good, 8.75 h)	89.7° 21:15	11.03	2%	127.0°
2028-11-18 Sat	100	—	unknown	18:35–03:20 (good, 8.75 h)	89.5° 21:10	11.06	7%	115.5°
2028-11-19 Sun	100	—	unknown	18:35–03:15 (good, 8.67 h)	89.5° 21:10	11.08	14%	103.9°
2028-11-20 Mon	100	—	unknown	18:35–03:15 (good, 8.67 h)	89.7° 21:05	11.11	21%	92.5°
2028-11-21 Tue	100	—	unknown	18:35–03:10 (good, 8.58 h)	89.7° 21:00	11.13	30%	81.4°
2028-11-22 Wed	100	—	unknown	18:35–03:05 (good, 8.5 h)	89.6° 20:55	11.16	40%	70.7°
2028-11-23 Thu	99	—	unknown	18:35–03:00 (good, 8.42 h)	89.5° 20:50	11.18	49%	60.4°
2028-11-24 Fri	91	—	unknown	18:35–02:55 (good, 8.33 h)	89.6° 20:50	11.2	59%	50.7°
2028-11-25 Sat	84	—	unknown	21:35–02:55 (good, 5.33 h)	89.7° 20:45	11.22	68%	41.8°
2028-11-26 Sun	64	—	unknown	02:40–02:50 (good, 0.17 h)	89.7° 20:40	11.25	76%	34.4°
2028-11-27 Mon	42	—	unknown	18:35–03:05 (marginal, 8.5 h)	89.6° 20:35	11.27	84%	29.4°
2028-11-28 Tue	30	—	unknown	18:35–02:45 (marginal, 8.17 h)	89.5° 20:35	11.29	90%	28.5°
2028-11-29 Wed	27	—	unknown	18:35–20:50 (marginal, 2.25 h)	89.6° 20:30	11.3	95%	32.2°
2028-11-30 Thu	32	—	unknown	18:35–22:35 (marginal, 4.0 h)	89.7° 20:25	11.32	98%	39.3°
2028-12-01 Fri	44	—	unknown	18:35–01:50 (marginal, 7.25 h)	89.7° 20:20	11.34	100%	48.6°
2028-12-02 Sat	63	—	unknown	18:35–19:15 (good, 0.67 h)	89.6° 20:15	11.36	99%	59.1°
2028-12-03 Sun	73	—	unknown	18:35–21:50 (good, 3.25 h)	89.5° 20:15	11.37	96%	70.3°
2028-12-04 Mon	100	—	unknown	18:35–00:00 (good, 5.42 h)	89.7° 20:10	11.39	91%	82.0°
2028-12-05 Tue	100	—	unknown	18:35–01:30 (good, 6.92 h)	89.7° 20:05	11.4	84%	94.0°
2028-12-06 Wed	100	—	unknown	18:35–01:50 (good, 7.25 h)	89.7° 20:00	11.41	75%	106.1°
2028-12-07 Thu	100	—	unknown	18:35–01:55 (good, 7.33 h)	89.5° 19:55	11.43	65%	118.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2028-11-08&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.