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.

2032-05-26astronomy score per night — click a bar for that night2032-06-24

night of	weather	overall	best window	highest	dark h	Moon	Moon sep.
2032-05-26 Wed	—	unknown	—	42.9° 14:40	5.01	96%	154.5°
2032-05-27 Thu	—	unknown	—	42.9° 14:35	4.97	90%	148.6°
2032-05-28 Fri	—	unknown	—	42.9° 14:30	4.93	82%	138.7°
2032-05-29 Sat	—	unknown	—	42.9° 14:30	4.89	72%	127.1°
2032-05-30 Sun	—	unknown	—	42.9° 14:25	4.85	61%	114.6°
2032-05-31 Mon	—	unknown	—	42.9° 14:20	4.81	49%	101.9°
2032-06-01 Tue	—	unknown	—	42.9° 14:15	4.78	38%	89.2°
2032-06-02 Wed	—	unknown	—	42.9° 14:10	4.74	28%	76.7°
2032-06-03 Thu	—	unknown	—	42.9° 14:10	4.71	18%	64.4°
2032-06-04 Fri	—	unknown	—	42.9° 14:05	4.68	11%	52.7°
2032-06-05 Sat	—	unknown	—	42.9° 14:00	4.65	5%	41.8°
2032-06-06 Sun	—	unknown	—	42.9° 13:55	4.62	1%	32.6°
2032-06-07 Mon	—	unknown	—	42.9° 13:50	4.59	0%	26.4°
2032-06-08 Tue	—	unknown	—	42.9° 13:50	4.57	1%	25.3°
2032-06-09 Wed	—	unknown	—	42.9° 13:45	4.54	4%	29.7°
2032-06-10 Thu	—	unknown	—	42.9° 13:40	4.52	8%	37.4°
2032-06-11 Fri	—	unknown	—	42.9° 13:35	4.5	14%	46.7°
2032-06-12 Sat	—	unknown	—	42.9° 13:35	4.49	22%	56.7°
2032-06-13 Sun	—	unknown	—	42.9° 13:30	4.47	30%	67.1°
2032-06-14 Mon	—	unknown	—	42.9° 13:25	4.46	39%	77.7°
2032-06-15 Tue	—	unknown	—	42.9° 13:20	4.45	48%	88.5°
2032-06-16 Wed	—	unknown	—	42.9° 13:15	4.44	58%	99.4°
2032-06-17 Thu	—	unknown	—	42.9° 13:15	4.43	67%	110.5°
2032-06-18 Fri	—	unknown	—	42.9° 13:10	4.43	76%	121.6°
2032-06-19 Sat	—	unknown	—	42.9° 13:05	4.42	85%	132.6°
2032-06-20 Sun	—	unknown	—	42.9° 13:00	4.42	92%	143.0°
2032-06-21 Mon	—	unknown	—	42.9° 12:55	4.42	97%	151.4°
2032-06-22 Tue	—	unknown	—	42.9° 12:55	4.43	100%	155.0°
2032-06-23 Wed	—	unknown	—	42.9° 12:50	4.43	100%	151.3°
2032-06-24 Thu	—	unknown	—	42.9° 12:45	4.44	97%	142.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2032-05-26&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.