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: 10-10 (100), 10-11 (100), 10-12 (100), 10-13 (100), 10-14 (100) — by astronomy; check the weather when the night is within four days.

2036-10-07astronomy score per night — click a bar for that night2036-11-05

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-10-07 Tue	58	—	unknown	19:55–05:55 (marginal, 10.0 h)	89.5° 00:55	9.49	93%	41.6°
2036-10-08 Wed	91	—	unknown	20:25–23:00 (good, 2.58 h)	89.6° 00:55	9.53	87%	47.7°
2036-10-09 Thu	96	—	unknown	20:25–01:25 (good, 5.0 h)	89.8° 00:50	9.58	79%	55.8°
2036-10-10 Fri	100	—	unknown	20:20–04:20 (good, 8.0 h)	89.8° 00:45	9.63	70%	65.3°
2036-10-11 Sat	100	—	unknown	20:20–06:00 (good, 9.67 h)	89.6° 00:40	9.67	59%	75.6°
2036-10-12 Sun	100	—	unknown	20:20–06:00 (good, 9.67 h)	89.5° 00:40	9.71	48%	86.4°
2036-10-13 Mon	100	—	unknown	20:15–06:05 (good, 9.83 h)	89.7° 00:35	9.76	37%	97.5°
2036-10-14 Tue	100	—	unknown	20:15–06:05 (good, 9.83 h)	89.8° 00:30	9.8	26%	108.6°
2036-10-15 Wed	100	—	unknown	20:15–06:05 (good, 9.83 h)	89.7° 00:25	9.85	17%	119.2°
2036-10-16 Thu	100	—	unknown	20:10–06:05 (good, 9.92 h)	89.6° 00:20	9.89	9%	128.8°
2036-10-17 Fri	100	—	unknown	20:10–06:05 (good, 9.92 h)	89.6° 00:20	9.93	3%	136.5°
2036-10-18 Sat	100	—	unknown	20:10–06:10 (good, 10.0 h)	89.7° 00:15	9.97	1%	141.1°
2036-10-19 Sun	100	—	unknown	20:10–06:10 (good, 10.0 h)	89.8° 00:10	10.02	0%	141.5°
2036-10-20 Mon	100	—	unknown	20:05–06:10 (good, 10.08 h)	89.7° 00:05	10.06	3%	137.7°
2036-10-21 Tue	100	—	unknown	20:05–06:10 (good, 10.08 h)	89.5° 00:00	10.1	7%	131.1°
2036-10-22 Wed	100	—	unknown	20:05–06:05 (good, 10.0 h)	89.6° 00:00	10.14	14%	122.8°
2036-10-23 Thu	100	—	unknown	20:05–06:05 (good, 10.0 h)	89.7° 23:55	10.18	21%	113.7°
2036-10-24 Fri	100	—	unknown	20:00–06:00 (good, 10.0 h)	89.8° 23:50	10.22	30%	104.3°
2036-10-25 Sat	100	—	unknown	20:00–04:55 (good, 9.92 h)	89.6° 23:45	10.26	39%	94.9°
2036-10-26 Sun	100	—	unknown	19:00–04:50 (good, 9.83 h)	89.5° 22:45	10.3	49%	85.5°
2036-10-27 Mon	100	—	unknown	18:55–04:45 (good, 9.83 h)	89.7° 22:40	10.34	58%	76.3°
2036-10-28 Tue	100	—	unknown	18:55–04:45 (good, 9.83 h)	89.8° 22:35	10.37	67%	67.3°
2036-10-29 Wed	95	—	unknown	18:55–04:40 (good, 9.75 h)	89.7° 22:30	10.41	76%	58.7°
2036-10-30 Thu	88	—	unknown	23:55–04:35 (good, 4.67 h)	89.6° 22:25	10.45	83%	50.9°
2036-10-31 Fri	81	—	unknown	03:50–04:30 (good, 0.67 h)	89.6° 22:25	10.49	90%	44.3°
2036-11-01 Sat	47	—	unknown	18:50–05:00 (marginal, 10.17 h)	89.7° 22:20	10.52	95%	39.7°
2036-11-02 Sun	47	—	unknown	18:50–04:30 (marginal, 9.67 h)	89.8° 22:15	10.56	98%	38.2°
2036-11-03 Mon	50	—	unknown	18:50–04:10 (marginal, 9.33 h)	89.7° 22:10	10.59	100%	40.2°
2036-11-04 Tue	58	—	unknown	18:50–04:00 (marginal, 9.17 h)	89.5° 22:05	10.63	99%	45.6°
2036-11-05 Wed	66	—	unknown	18:45–20:25 (good, 1.67 h)	89.6° 22:05	10.66	96%	53.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-10-07&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.