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.

Best nights for Andromeda Galaxy: 07-04 (66), 07-02 (65), 07-03 (65), 07-01 (63), 06-30 (62) — by astronomy; check the weather when the night is within four days.

2047-06-05astronomy score per night — click a bar for that night2047-07-04

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-06-05 Wed	21	—	unknown	03:15–03:40 (good, 0.42 h)	89.6° 09:10	4.67	93%	147.0°
2047-06-06 Thu	21	—	unknown	03:10–03:40 (good, 0.5 h)	89.8° 09:05	4.64	98%	137.8°
2047-06-07 Fri	20	—	unknown	03:05–03:40 (good, 0.58 h)	89.8° 09:00	4.61	100%	126.4°
2047-06-08 Sat	20	—	unknown	03:05–03:40 (good, 0.58 h)	89.7° 08:55	4.58	99%	114.2°
2047-06-09 Sun	18	—	unknown	03:10–03:40 (good, 0.5 h)	89.5° 08:50	4.56	95%	101.7°
2047-06-10 Mon	17	—	unknown	03:15–03:40 (good, 0.42 h)	89.7° 08:50	4.54	90%	89.5°
2047-06-11 Tue	16	—	unknown	02:10–03:40 (marginal, 1.5 h)	89.8° 08:45	4.52	82%	77.6°
2047-06-12 Wed	16	—	unknown	02:05–03:40 (marginal, 1.58 h)	89.8° 08:40	4.5	73%	66.2°
2047-06-13 Thu	17	—	unknown	02:00–03:40 (marginal, 1.67 h)	89.7° 08:35	4.48	64%	55.6°
2047-06-14 Fri	19	—	unknown	03:00–03:40 (good, 0.67 h)	89.5° 08:35	4.47	54%	45.8°
2047-06-15 Sat	22	—	unknown	02:50–03:40 (good, 0.83 h)	89.7° 08:30	4.45	44%	37.4°
2047-06-16 Sun	25	—	unknown	02:40–03:40 (good, 1.0 h)	89.8° 08:25	4.44	35%	31.1°
2047-06-17 Mon	30	—	unknown	02:30–03:40 (good, 1.17 h)	89.8° 08:20	4.44	26%	28.3°
2047-06-18 Tue	35	—	unknown	02:15–03:40 (good, 1.42 h)	89.6° 08:15	4.43	18%	29.8°
2047-06-19 Wed	40	—	unknown	02:10–03:40 (good, 1.5 h)	89.6° 08:15	4.42	12%	35.1°
2047-06-20 Thu	44	—	unknown	02:05–03:40 (good, 1.58 h)	89.8° 08:10	4.42	6%	42.9°
2047-06-21 Fri	45	—	unknown	02:00–03:40 (good, 1.67 h)	89.8° 08:05	4.42	2%	52.2°
2047-06-22 Sat	46	—	unknown	01:55–03:40 (good, 1.75 h)	89.7° 08:00	4.42	0%	62.4°
2047-06-23 Sun	48	—	unknown	01:55–03:40 (good, 1.75 h)	89.5° 07:55	4.43	0%	73.2°
2047-06-24 Mon	50	—	unknown	01:50–03:40 (good, 1.83 h)	89.6° 07:55	4.44	2%	84.3°
2047-06-25 Tue	52	—	unknown	01:45–03:40 (good, 1.92 h)	89.8° 07:50	4.44	6%	95.8°
2047-06-26 Wed	53	—	unknown	01:40–03:40 (good, 2.0 h)	89.8° 07:45	4.45	13%	107.3°
2047-06-27 Thu	55	—	unknown	01:40–03:40 (good, 2.0 h)	89.7° 07:40	4.47	21%	118.8°
2047-06-28 Fri	57	—	unknown	01:35–03:40 (good, 2.08 h)	89.5° 07:40	4.48	30%	129.9°
2047-06-29 Sat	59	—	unknown	01:30–03:40 (good, 2.17 h)	89.7° 07:35	4.5	41%	140.1°
2047-06-30 Sun	62	—	unknown	01:25–03:45 (good, 2.33 h)	89.8° 07:30	4.52	52%	148.2°
2047-07-01 Mon	63	—	unknown	01:20–03:45 (good, 2.42 h)	89.8° 07:25	4.54	64%	151.8°
2047-07-02 Tue	65	—	unknown	01:25–03:45 (good, 2.33 h)	89.6° 07:20	4.56	74%	149.2°
2047-07-03 Wed	65	—	unknown	01:20–03:45 (good, 2.42 h)	89.6° 07:20	4.58	84%	141.4°
2047-07-04 Thu	66	—	unknown	01:20–03:45 (good, 2.42 h)	89.8° 07:15	4.61	92%	130.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-06-05&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.