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.

2046-10-04astronomy score per night — click a bar for that night2046-11-02

night of	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-10-04 Thu	—	unknown	—	50.1° 13:00	9.33	30%	72.6°
2046-10-05 Fri	—	unknown	—	50.1° 12:55	9.38	40%	85.9°
2046-10-06 Sat	—	unknown	—	50.1° 12:50	9.42	51%	98.8°
2046-10-07 Sun	—	unknown	—	50.1° 12:50	9.47	61%	111.2°
2046-10-08 Mon	—	unknown	—	50.1° 12:45	9.52	70%	123.4°
2046-10-09 Tue	—	unknown	—	50.1° 12:40	9.56	78%	135.3°
2046-10-10 Wed	—	unknown	—	50.1° 12:35	9.61	86%	146.8°
2046-10-11 Thu	—	unknown	—	50.1° 12:30	9.65	92%	157.9°
2046-10-12 Fri	—	unknown	—	50.1° 12:30	9.7	96%	167.6°
2046-10-13 Sat	—	unknown	—	50.1° 12:25	9.74	99%	170.0°
2046-10-14 Sun	—	unknown	—	50.1° 12:20	9.78	100%	162.0°
2046-10-15 Mon	—	unknown	—	50.1° 12:15	9.83	99%	151.2°
2046-10-16 Tue	—	unknown	—	50.1° 12:10	9.87	96%	139.8°
2046-10-17 Wed	—	unknown	—	50.1° 12:10	9.91	92%	128.0°
2046-10-18 Thu	—	unknown	—	50.1° 12:00	9.96	86%	115.9°
2046-10-19 Fri	—	unknown	—	50.1° 12:00	10.0	78%	103.7°
2046-10-20 Sat	—	unknown	—	50.1° 11:55	10.04	70%	91.2°
2046-10-21 Sun	—	unknown	—	50.1° 11:50	10.08	60%	78.4°
2046-10-22 Mon	—	unknown	—	50.1° 11:45	10.12	49%	65.3°
2046-10-23 Tue	—	unknown	—	50.1° 11:40	10.16	38%	51.9°
2046-10-24 Wed	—	unknown	—	50.1° 11:35	10.2	28%	38.2°
2046-10-25 Thu	—	unknown	—	50.1° 11:35	10.24	18%	24.5°
2046-10-26 Fri	—	unknown	—	50.1° 11:30	10.28	10%	12.3°
2046-10-27 Sat	—	unknown	—	50.1° 10:25	10.32	4%	11.7°
2046-10-28 Sun	—	unknown	—	50.1° 10:20	10.36	1%	24.0°
2046-10-29 Mon	—	unknown	—	50.1° 10:15	10.4	0%	38.3°
2046-10-30 Tue	—	unknown	—	50.1° 10:15	10.43	3%	52.7°
2046-10-31 Wed	—	unknown	—	50.1° 10:10	10.47	8%	67.0°
2046-11-01 Thu	—	unknown	—	50.1° 10:05	10.51	16%	80.9°
2046-11-02 Fri	—	unknown	—	50.1° 10:00	10.54	25%	94.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-10-04&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.