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.

2032-03-21astronomy score per night — click a bar for that night2032-04-19

night of	weather	overall	best window	highest	dark h	Moon	Moon sep.
2032-03-21 Sun	—	unknown	—	89.5° 13:05	8.64	78%	99.2°
2032-03-22 Mon	—	unknown	—	89.6° 13:05	8.59	85%	109.0°
2032-03-23 Tue	—	unknown	—	89.7° 13:00	8.54	91%	118.7°
2032-03-24 Wed	—	unknown	—	89.7° 12:55	8.48	96%	127.9°
2032-03-25 Thu	—	unknown	—	89.6° 12:50	8.43	99%	136.3°
2032-03-26 Fri	—	unknown	—	89.5° 12:50	8.38	100%	143.2°
2032-03-27 Sat	—	unknown	—	89.7° 12:45	8.32	99%	147.3°
2032-03-28 Sun	—	unknown	—	89.8° 13:40	8.27	96%	147.3°
2032-03-29 Mon	—	unknown	—	89.7° 13:35	8.22	92%	143.1°
2032-03-30 Tue	—	unknown	—	89.5° 13:30	8.16	85%	135.8°
2032-03-31 Wed	—	unknown	—	89.6° 13:30	8.11	76%	126.4°
2032-04-01 Thu	—	unknown	—	89.7° 13:25	8.05	66%	115.8°
2032-04-02 Fri	—	unknown	—	89.7° 13:20	8.0	56%	104.5°
2032-04-03 Sat	—	unknown	—	89.6° 13:15	7.94	44%	92.7°
2032-04-04 Sun	—	unknown	—	89.5° 13:10	7.89	33%	80.6°
2032-04-05 Mon	—	unknown	—	89.6° 13:10	7.83	23%	68.6°
2032-04-06 Tue	—	unknown	—	89.7° 13:05	7.77	14%	57.0°
2032-04-07 Wed	—	unknown	—	89.7° 13:00	7.72	6%	46.3°
2032-04-08 Thu	—	unknown	—	89.6° 12:55	7.66	2%	37.7°
2032-04-09 Fri	—	unknown	—	89.5° 12:55	7.61	0%	32.7°
2032-04-10 Sat	—	unknown	—	89.7° 12:50	7.55	1%	33.0°
2032-04-11 Sun	—	unknown	—	89.8° 12:45	7.49	4%	38.1°
2032-04-12 Mon	—	unknown	—	89.7° 12:40	7.43	10%	46.1°
2032-04-13 Tue	—	unknown	—	89.5° 12:35	7.38	16%	55.5°
2032-04-14 Wed	—	unknown	—	89.6° 12:35	7.32	25%	65.5°
2032-04-15 Thu	—	unknown	—	89.7° 12:30	7.26	34%	75.7°
2032-04-16 Fri	—	unknown	—	89.7° 12:25	7.2	43%	85.9°
2032-04-17 Sat	—	unknown	—	89.7° 12:20	7.15	53%	96.0°
2032-04-18 Sun	—	unknown	—	89.5° 12:15	7.09	62%	105.9°
2032-04-19 Mon	—	unknown	—	89.6° 12:15	7.03	71%	115.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2032-03-21&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.