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.

2032-06-19astronomy score per night — click a bar for that night2032-07-18

night of	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2032-06-25 Fri	—	unknown	—	42.9° 12:40	4.45	91%	130.7°
2032-06-26 Sat	—	unknown	—	42.9° 12:40	4.46	84%	118.0°
2032-06-27 Sun	—	unknown	—	42.9° 12:35	4.48	74%	105.1°
2032-06-28 Mon	—	unknown	—	42.9° 12:30	4.49	63%	92.1°
2032-06-29 Tue	—	unknown	—	42.9° 12:25	4.51	52%	79.3°
2032-06-30 Wed	—	unknown	—	42.9° 12:20	4.53	41%	67.0°
2032-07-01 Thu	—	unknown	—	42.9° 12:20	4.55	30%	55.2°
2032-07-02 Fri	—	unknown	—	42.9° 12:15	4.57	21%	44.2°
2032-07-03 Sat	—	unknown	—	42.9° 12:10	4.6	13%	34.6°
2032-07-04 Sun	—	unknown	—	42.9° 12:05	4.63	7%	27.6°
2032-07-05 Mon	—	unknown	—	42.9° 12:00	4.65	3%	25.0°
2032-07-06 Tue	—	unknown	—	42.9° 11:55	4.68	1%	28.0°
2032-07-07 Wed	—	unknown	—	42.9° 11:50	4.72	0%	35.0°
2032-07-08 Thu	—	unknown	—	42.9° 11:45	4.75	2%	43.9°
2032-07-09 Fri	—	unknown	—	42.9° 11:45	4.78	5%	53.8°
2032-07-10 Sat	—	unknown	—	42.9° 11:40	4.82	10%	64.1°
2032-07-11 Sun	—	unknown	—	42.9° 11:35	4.86	16%	74.6°
2032-07-12 Mon	—	unknown	—	42.9° 11:30	4.9	24%	85.3°
2032-07-13 Tue	—	unknown	—	42.9° 11:25	4.94	32%	96.1°
2032-07-14 Wed	—	unknown	—	42.9° 11:25	4.98	42%	107.0°
2032-07-15 Thu	—	unknown	—	42.9° 11:20	5.02	52%	117.9°
2032-07-16 Fri	—	unknown	—	42.9° 11:15	5.07	62%	128.8°
2032-07-17 Sat	—	unknown	—	42.9° 11:10	5.11	72%	139.3°
2032-07-18 Sun	—	unknown	—	42.9° 11:05	5.16	81%	148.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2032-06-19&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.