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.

2047-06-07astronomy score per night — click a bar for that night2047-07-06

night of	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-06-07 Fri	—	unknown	—	72.6° 12:05	4.61	100%	164.8°
2047-06-08 Sat	—	unknown	—	72.6° 12:00	4.58	99%	150.1°
2047-06-09 Sun	—	unknown	—	72.6° 12:00	4.56	95%	135.7°
2047-06-10 Mon	—	unknown	—	72.6° 11:50	4.54	90%	121.8°
2047-06-11 Tue	—	unknown	—	72.6° 11:50	4.52	82%	108.3°
2047-06-12 Wed	—	unknown	—	72.6° 11:45	4.5	73%	95.2°
2047-06-13 Thu	—	unknown	—	72.6° 11:40	4.48	64%	82.5°
2047-06-14 Fri	—	unknown	—	72.6° 11:35	4.47	54%	70.1°
2047-06-15 Sat	—	unknown	—	72.6° 11:30	4.45	44%	58.0°
2047-06-16 Sun	—	unknown	—	72.6° 11:30	4.44	35%	46.1°
2047-06-17 Mon	—	unknown	—	72.6° 11:25	4.44	26%	34.3°
2047-06-18 Tue	—	unknown	—	72.6° 11:20	4.43	18%	22.4°
2047-06-19 Wed	—	unknown	—	72.6° 11:15	4.42	12%	10.6°
2047-06-20 Thu	—	unknown	—	72.6° 11:10	4.42	6%	1.5°
2047-06-21 Fri	—	unknown	—	72.6° 11:10	4.42	2%	13.6°
2047-06-22 Sat	—	unknown	—	72.6° 11:05	4.42	0%	25.9°
2047-06-23 Sun	—	unknown	—	72.6° 11:00	4.43	0%	38.4°
2047-06-24 Mon	—	unknown	—	72.6° 10:55	4.44	2%	51.2°
2047-06-25 Tue	—	unknown	—	72.6° 10:55	4.44	6%	64.1°
2047-06-26 Wed	—	unknown	—	72.6° 10:50	4.45	13%	77.3°
2047-06-27 Thu	—	unknown	—	72.6° 10:45	4.47	21%	90.7°
2047-06-28 Fri	—	unknown	—	72.6° 10:40	4.48	30%	104.3°
2047-06-29 Sat	—	unknown	—	72.6° 10:35	4.5	41%	118.1°
2047-06-30 Sun	—	unknown	—	72.6° 10:35	4.52	52%	132.1°
2047-07-01 Mon	—	unknown	—	72.6° 10:30	4.54	64%	146.3°
2047-07-02 Tue	—	unknown	—	72.6° 10:25	4.56	74%	160.7°
2047-07-03 Wed	—	unknown	—	72.6° 10:20	4.58	84%	175.2°
2047-07-04 Thu	—	unknown	—	72.6° 10:15	4.61	92%	170.3°
2047-07-05 Fri	—	unknown	—	72.6° 10:15	4.64	97%	155.8°
2047-07-06 Sat	—	unknown	—	72.6° 10:10	4.67	100%	141.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-06-07&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.