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: 11-23 (100), 11-24 (100), 11-25 (100), 11-26 (100), 11-27 (100) — by astronomy; check the weather when the night is within four days.

2029-11-18astronomy score per night — click a bar for that night2029-12-17

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-11-18 Sun	29	—	unknown	00:20–03:15 (marginal, 2.92 h)	89.5° 21:15	11.05	95%	29.5°
2029-11-19 Mon	31	—	unknown	18:35–21:10 (marginal, 2.58 h)	89.7° 21:10	11.08	98%	33.6°
2029-11-20 Tue	40	—	unknown	18:35–23:30 (marginal, 4.92 h)	89.7° 21:05	11.1	100%	40.6°
2029-11-21 Wed	55	—	unknown	18:35–02:40 (marginal, 8.08 h)	89.7° 21:00	11.13	100%	49.3°
2029-11-22 Thu	68	—	unknown	18:35–20:10 (good, 1.58 h)	89.5° 20:55	11.15	97%	58.9°
2029-11-23 Fri	100	—	unknown	18:35–22:40 (good, 4.08 h)	89.6° 20:55	11.17	93%	69.2°
2029-11-24 Sat	100	—	unknown	18:35–00:40 (good, 6.08 h)	89.7° 20:50	11.2	87%	79.9°
2029-11-25 Sun	100	—	unknown	18:35–02:05 (good, 7.5 h)	89.7° 20:45	11.22	80%	90.8°
2029-11-26 Mon	100	—	unknown	18:35–02:30 (good, 7.92 h)	89.6° 20:40	11.24	71%	101.9°
2029-11-27 Tue	100	—	unknown	18:35–02:35 (good, 8.0 h)	89.5° 20:40	11.26	61%	113.1°
2029-11-28 Wed	100	—	unknown	18:35–02:35 (good, 8.0 h)	89.6° 20:35	11.28	51%	124.2°
2029-11-29 Thu	100	—	unknown	18:35–02:35 (good, 8.0 h)	89.7° 20:30	11.3	40%	134.9°
2029-11-30 Fri	100	—	unknown	18:35–02:30 (good, 7.92 h)	89.7° 20:25	11.32	29%	144.2°
2029-12-01 Sat	100	—	unknown	18:35–02:30 (good, 7.92 h)	89.6° 20:20	11.34	19%	150.2°
2029-12-02 Sun	100	—	unknown	18:35–02:25 (good, 7.83 h)	89.5° 20:20	11.35	11%	150.4°
2029-12-03 Mon	100	—	unknown	18:35–02:25 (good, 7.83 h)	89.7° 20:15	11.37	4%	144.3°
2029-12-04 Tue	100	—	unknown	18:35–02:20 (good, 7.75 h)	89.7° 20:10	11.38	1%	134.4°
2029-12-05 Wed	100	—	unknown	18:35–02:15 (good, 7.67 h)	89.7° 20:05	11.4	0%	122.6°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-11-18&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.