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: 11-18 (100), 11-19 (100), 11-20 (100), 11-21 (100), 11-22 (100) — by astronomy; check the weather when the night is within four days.

2046-11-18astronomy score per night — click a bar for that night2046-12-17

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-11-18 Sun	100	—	unknown	18:40–02:45 (good, 8.08 h)	89.8° 21:15	11.05	74%	89.8°
2046-11-19 Mon	100	—	unknown	18:35–03:00 (good, 8.42 h)	89.8° 21:10	11.07	64%	101.5°
2046-11-20 Tue	100	—	unknown	18:35–03:05 (good, 8.5 h)	89.7° 21:05	11.1	54%	113.4°
2046-11-21 Wed	100	—	unknown	18:35–03:05 (good, 8.5 h)	89.5° 21:05	11.12	43%	125.0°
2046-11-22 Thu	100	—	unknown	18:35–03:05 (good, 8.5 h)	89.7° 21:00	11.15	32%	136.1°
2046-11-23 Fri	100	—	unknown	18:35–03:05 (good, 8.5 h)	89.8° 20:55	11.17	21%	145.5°
2046-11-24 Sat	100	—	unknown	18:35–03:00 (good, 8.42 h)	89.8° 20:50	11.19	12%	151.1°
2046-11-25 Sun	100	—	unknown	18:35–02:55 (good, 8.33 h)	89.6° 20:45	11.22	6%	150.5°
2046-11-26 Mon	100	—	unknown	18:35–02:50 (good, 8.25 h)	89.6° 20:45	11.24	2%	143.9°
2046-11-27 Tue	100	—	unknown	18:35–02:50 (good, 8.25 h)	89.7° 20:40	11.26	0%	133.9°
2046-11-28 Wed	100	—	unknown	18:35–02:45 (good, 8.17 h)	89.8° 20:35	11.28	1%	122.5°
2046-11-29 Thu	100	—	unknown	18:35–02:40 (good, 8.08 h)	89.7° 20:30	11.3	5%	110.6°
2046-11-30 Fri	100	—	unknown	18:35–02:35 (good, 8.0 h)	89.6° 20:25	11.32	11%	98.7°
2046-12-01 Sat	100	—	unknown	18:35–02:30 (good, 7.92 h)	89.6° 20:25	11.33	19%	87.0°
2046-12-02 Sun	100	—	unknown	18:35–02:30 (good, 7.92 h)	89.8° 20:20	11.35	27%	75.8°
2046-12-03 Mon	100	—	unknown	18:35–02:25 (good, 7.83 h)	89.8° 20:15	11.37	36%	65.0°
2046-12-04 Tue	94	—	unknown	18:35–02:20 (good, 7.75 h)	89.7° 20:10	11.38	46%	54.8°
2046-12-05 Wed	87	—	unknown	18:35–02:15 (good, 7.67 h)	89.5° 20:10	11.4	56%	45.4°
2046-12-06 Thu	79	—	unknown	21:40–02:15 (good, 4.58 h)	89.7° 20:05	11.41	65%	37.2°
2046-12-07 Fri	52	—	unknown	18:35–02:40 (marginal, 8.08 h)	89.8° 20:00	11.42	74%	31.0°
2046-12-08 Sat	38	—	unknown	18:35–02:20 (marginal, 7.75 h)	89.8° 19:55	11.43	81%	28.2°
2046-12-09 Sun	27	—	unknown	18:35–01:55 (marginal, 7.33 h)	89.6° 19:50	11.44	88%	29.9°
2046-12-10 Mon	27	—	unknown	18:35–01:30 (marginal, 6.92 h)	89.6° 19:50	11.45	94%	35.5°
2046-12-11 Tue	32	—	unknown	18:35–00:10 (marginal, 5.58 h)	89.7° 19:45	11.46	98%	43.7°
2046-12-12 Wed	44	—	unknown	18:35–01:25 (marginal, 6.83 h)	89.8° 19:40	11.47	100%	53.4°
2046-12-13 Thu	62	—	unknown	18:35–19:30 (good, 0.92 h)	89.7° 19:35	11.48	100%	64.1°
2046-12-14 Fri	74	—	unknown	18:35–22:20 (good, 3.75 h)	89.6° 19:30	11.49	98%	75.4°
2046-12-15 Sat	100	—	unknown	18:35–23:45 (good, 5.17 h)	89.6° 19:30	11.49	93%	87.1°
2046-12-16 Sun	100	—	unknown	18:35–01:05 (good, 6.5 h)	89.8° 19:25	11.5	87%	99.0°
2046-12-17 Mon	100	—	unknown	18:35–01:15 (good, 6.67 h)	89.8° 19:20	11.5	78%	110.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-11-18&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.