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: 12-06 (100), 12-07 (100), 12-08 (100), 12-09 (100), 12-10 (100) — by astronomy; check the weather when the night is within four days.

2029-12-06astronomy score per night — click a bar for that night2030-01-04

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-12-06 Thu	100	—	unknown	18:35–02:10 (good, 7.58 h)	89.5° 20:00	11.41	2%	110.1°
2029-12-07 Fri	100	—	unknown	18:35–02:05 (good, 7.5 h)	89.6° 20:00	11.42	7%	97.6°
2029-12-08 Sat	100	—	unknown	18:35–02:05 (good, 7.5 h)	89.7° 19:55	11.44	14%	85.3°
2029-12-09 Sun	100	—	unknown	18:35–02:00 (good, 7.42 h)	89.7° 19:50	11.45	23%	73.5°
2029-12-10 Mon	100	—	unknown	18:35–01:55 (good, 7.33 h)	89.6° 19:45	11.46	32%	62.3°
2029-12-11 Tue	93	—	unknown	18:35–01:50 (good, 7.25 h)	89.5° 19:45	11.47	42%	51.9°
2029-12-12 Wed	85	—	unknown	18:35–01:45 (good, 7.17 h)	89.6° 19:40	11.47	52%	42.7°
2029-12-13 Thu	70	—	unknown	21:00–01:15 (good, 4.25 h)	89.7° 19:35	11.48	61%	35.0°
2029-12-14 Fri	52	—	unknown	18:35–02:10 (marginal, 7.58 h)	89.7° 19:30	11.49	70%	30.1°
2029-12-15 Sat	36	—	unknown	18:35–01:50 (marginal, 7.25 h)	89.6° 19:25	11.49	79%	29.0°
2029-12-16 Sun	28	—	unknown	18:35–01:30 (marginal, 6.92 h)	89.5° 19:25	11.5	86%	32.1°
2029-12-17 Mon	28	—	unknown	18:35–01:10 (marginal, 6.58 h)	89.7° 19:20	11.5	92%	38.4°
2029-12-18 Tue	33	—	unknown	18:35–01:00 (marginal, 6.42 h)	89.7° 19:15	11.5	96%	46.8°
2029-12-19 Wed	44	—	unknown	18:35–01:05 (marginal, 6.5 h)	89.7° 19:10	11.51	99%	56.3°
2029-12-20 Thu	59	—	unknown	18:35–19:30 (good, 0.92 h)	89.5° 19:05	11.51	100%	66.5°
2029-12-21 Fri	73	—	unknown	18:35–21:55 (good, 3.33 h)	89.6° 19:05	11.51	99%	77.2°
2029-12-22 Sat	100	—	unknown	18:35–23:15 (good, 4.67 h)	89.7° 19:00	11.51	96%	88.2°
2029-12-23 Sun	100	—	unknown	18:40–00:35 (good, 5.92 h)	89.7° 18:55	11.51	91%	99.4°
2029-12-24 Mon	100	—	unknown	18:40–00:40 (good, 6.0 h)	89.6° 18:50	11.5	84%	110.7°
2029-12-25 Tue	100	—	unknown	18:40–00:45 (good, 6.08 h)	89.5° 18:50	11.5	76%	121.8°
2029-12-26 Wed	100	—	unknown	18:40–00:45 (good, 6.08 h)	89.6° 18:45	11.49	66%	132.5°
2029-12-27 Thu	100	—	unknown	18:40–00:45 (good, 6.08 h)	89.7° 18:40	11.49	55%	142.0°
2029-12-28 Fri	100	—	unknown	18:40–00:45 (good, 6.08 h)	89.7° 18:35	11.48	44%	149.0°
2029-12-29 Sat	100	—	unknown	18:40–00:40 (good, 6.0 h)	89.6° 18:30	11.48	33%	151.1°
2029-12-30 Sun	100	—	unknown	18:40–00:35 (good, 5.92 h)	89.5° 18:30	11.47	23%	147.1°
2029-12-31 Mon	100	—	unknown	18:45–00:35 (good, 5.83 h)	89.7° 18:25	11.46	14%	138.5°
2030-01-01 Tue	100	—	unknown	18:45–00:30 (good, 5.75 h)	89.7° 18:20	11.45	6%	127.6°
2030-01-02 Wed	100	—	unknown	18:45–00:25 (good, 5.67 h)	89.7° 18:15	11.44	2%	115.6°
2030-01-03 Thu	100	—	unknown	18:45–00:20 (good, 5.58 h)	89.5° 18:10	11.43	0%	103.1°
2030-01-04 Fri	100	—	unknown	18:45–00:15 (good, 5.5 h)	89.6° 18:10	11.42	1%	90.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-12-06&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.