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: 11-20 (100), 11-21 (100), 11-22 (100), 11-23 (100), 12-05 (100) — by astronomy; check the weather when the night is within four days.

2047-11-20astronomy score per night — click a bar for that night2047-12-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-11-20 Wed	100	—	unknown	18:35–03:15 (good, 8.67 h)	89.5° 21:10	11.09	16%	99.9°
2047-11-21 Thu	100	—	unknown	18:35–03:15 (good, 8.67 h)	89.7° 21:05	11.12	25%	87.5°
2047-11-22 Fri	100	—	unknown	18:35–03:10 (good, 8.58 h)	89.8° 21:00	11.14	35%	75.6°
2047-11-23 Sat	100	—	unknown	18:35–03:05 (good, 8.5 h)	89.8° 20:55	11.17	46%	64.2°
2047-11-24 Sun	94	—	unknown	18:35–03:00 (good, 8.42 h)	89.6° 20:50	11.19	56%	53.6°
2047-11-25 Mon	86	—	unknown	18:35–02:55 (good, 8.33 h)	89.6° 20:50	11.21	65%	44.0°
2047-11-26 Tue	73	—	unknown	02:30–02:55 (good, 0.42 h)	89.7° 20:45	11.23	74%	35.9°
2047-11-27 Wed	46	—	unknown	18:35–03:10 (marginal, 8.58 h)	89.8° 20:40	11.25	82%	30.3°
2047-11-28 Thu	32	—	unknown	18:35–02:50 (marginal, 8.25 h)	89.7° 20:35	11.27	89%	28.5°
2047-11-29 Fri	27	—	unknown	18:35–20:50 (marginal, 2.25 h)	89.6° 20:30	11.29	94%	31.0°
2047-11-30 Sat	30	—	unknown	18:35–21:50 (marginal, 3.25 h)	89.6° 20:30	11.31	98%	37.0°
2047-12-01 Sun	39	—	unknown	18:35–00:25 (marginal, 5.83 h)	89.8° 20:25	11.33	100%	45.0°
2047-12-02 Mon	55	—	unknown	18:35–02:05 (marginal, 7.5 h)	89.8° 20:20	11.35	100%	54.3°
2047-12-03 Tue	68	—	unknown	18:35–20:20 (good, 1.75 h)	89.7° 20:15	11.36	98%	64.3°
2047-12-04 Wed	77	—	unknown	18:35–23:05 (good, 4.5 h)	89.5° 20:10	11.38	95%	74.7°
2047-12-05 Thu	100	—	unknown	18:35–00:30 (good, 5.92 h)	89.7° 20:10	11.39	90%	85.4°
2047-12-06 Fri	100	—	unknown	18:35–01:45 (good, 7.17 h)	89.8° 20:05	11.41	83%	96.3°
2047-12-07 Sat	100	—	unknown	18:35–01:50 (good, 7.25 h)	89.8° 20:00	11.42	74%	107.3°
2047-12-08 Sun	100	—	unknown	18:35–01:55 (good, 7.33 h)	89.6° 19:55	11.43	65%	118.3°
2047-12-09 Mon	100	—	unknown	18:35–01:55 (good, 7.33 h)	89.6° 19:55	11.44	55%	129.1°
2047-12-10 Tue	100	—	unknown	18:35–01:55 (good, 7.33 h)	89.7° 19:50	11.45	44%	139.1°
2047-12-11 Wed	100	—	unknown	18:35–01:55 (good, 7.33 h)	89.8° 19:45	11.46	33%	147.3°
2047-12-12 Thu	100	—	unknown	18:35–01:50 (good, 7.25 h)	89.7° 19:40	11.47	22%	151.5°
2047-12-13 Fri	100	—	unknown	18:35–01:45 (good, 7.17 h)	89.6° 19:35	11.48	14%	149.3°
2047-12-14 Sat	100	—	unknown	18:35–01:40 (good, 7.08 h)	89.6° 19:35	11.48	6%	141.6°
2047-12-15 Sun	100	—	unknown	18:35–01:40 (good, 7.08 h)	89.8° 19:30	11.49	2%	130.7°
2047-12-16 Mon	100	—	unknown	18:35–01:35 (good, 7.0 h)	89.8° 19:25	11.5	0%	118.4°
2047-12-17 Tue	100	—	unknown	18:35–01:30 (good, 6.92 h)	89.7° 19:20	11.5	1%	105.6°
2047-12-18 Wed	100	—	unknown	18:35–01:25 (good, 6.83 h)	89.5° 19:15	11.5	5%	92.7°
2047-12-19 Thu	100	—	unknown	18:35–01:25 (good, 6.83 h)	89.7° 19:15	11.51	12%	80.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-11-20&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.