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: 07-08 (73), 07-07 (66), 07-06 (59), 07-05 (50), 06-22 (46) — by astronomy; check the weather when the night is within four days.

2037-06-09astronomy score per night — click a bar for that night2037-07-08

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2037-06-09 Tue	28	—	unknown	02:45–03:40 (good, 0.92 h)	89.8° 08:50	4.55	15%	38.9°
2037-06-10 Wed	30	—	unknown	02:40–03:40 (good, 1.0 h)	89.7° 08:45	4.53	9%	42.1°
2037-06-11 Thu	31	—	unknown	02:40–03:40 (good, 1.0 h)	89.5° 08:40	4.51	4%	48.1°
2037-06-12 Fri	33	—	unknown	02:35–03:40 (good, 1.08 h)	89.6° 08:40	4.49	1%	56.1°
2037-06-13 Sat	34	—	unknown	02:30–03:40 (good, 1.17 h)	89.8° 08:35	4.47	0%	65.6°
2037-06-14 Sun	35	—	unknown	02:25–03:40 (good, 1.25 h)	89.8° 08:30	4.46	2%	75.9°
2037-06-15 Mon	37	—	unknown	02:25–03:40 (good, 1.25 h)	89.6° 08:25	4.45	6%	86.8°
2037-06-16 Tue	38	—	unknown	02:20–03:40 (good, 1.33 h)	89.5° 08:25	4.44	13%	97.9°
2037-06-17 Wed	40	—	unknown	02:15–03:40 (good, 1.42 h)	89.7° 08:20	4.43	21%	108.8°
2037-06-18 Thu	41	—	unknown	02:10–03:40 (good, 1.5 h)	89.8° 08:15	4.43	32%	119.2°
2037-06-19 Fri	43	—	unknown	02:05–03:40 (good, 1.58 h)	89.7° 08:10	4.42	43%	128.5°
2037-06-20 Sat	44	—	unknown	02:05–03:40 (good, 1.58 h)	89.6° 08:05	4.42	54%	136.0°
2037-06-21 Sun	45	—	unknown	02:05–03:40 (good, 1.58 h)	89.6° 08:05	4.42	65%	140.6°
2037-06-22 Mon	46	—	unknown	02:00–03:40 (good, 1.67 h)	89.7° 08:00	4.43	76%	141.2°
2037-06-23 Tue	46	—	unknown	02:00–03:40 (good, 1.67 h)	89.8° 07:55	4.43	85%	137.7°
2037-06-24 Wed	43	—	unknown	02:00–03:40 (good, 1.67 h)	89.7° 07:50	4.44	92%	131.2°
2037-06-25 Thu	43	—	unknown	01:55–03:40 (good, 1.75 h)	89.5° 07:45	4.45	97%	122.9°
2037-06-26 Fri	41	—	unknown	01:55–03:40 (good, 1.75 h)	89.6° 07:45	4.46	99%	113.5°
2037-06-27 Sat	37	—	unknown	02:00–03:40 (good, 1.67 h)	89.7° 07:40	4.47	100%	103.8°
2037-06-28 Sun	33	—	unknown	02:00–03:40 (good, 1.67 h)	89.8° 07:35	4.49	98%	93.9°
2037-06-29 Mon	30	—	unknown	02:35–03:40 (good, 1.08 h)	89.6° 07:30	4.51	95%	84.1°
2037-06-30 Tue	29	—	unknown	03:10–03:45 (good, 0.58 h)	89.5° 07:30	4.52	89%	74.6°
2037-07-01 Wed	29	—	unknown	03:25–03:45 (good, 0.33 h)	89.7° 07:25	4.55	83%	65.6°
2037-07-02 Thu	30	—	unknown	03:15–03:45 (good, 0.5 h)	89.8° 07:20	4.57	75%	57.2°
2037-07-03 Fri	33	—	unknown	02:05–03:45 (good, 1.67 h)	89.7° 07:15	4.59	66%	49.8°
2037-07-04 Sat	38	—	unknown	01:35–03:45 (good, 2.17 h)	89.6° 07:10	4.62	57%	43.8°
2037-07-05 Sun	50	—	unknown	01:05–03:50 (good, 2.75 h)	89.5° 07:10	4.65	47%	39.8°
2037-07-06 Mon	59	—	unknown	01:00–03:50 (good, 2.83 h)	89.7° 07:05	4.68	38%	38.6°
2037-07-07 Tue	66	—	unknown	00:55–03:50 (good, 2.92 h)	89.8° 07:00	4.71	28%	40.7°
2037-07-08 Wed	73	—	unknown	00:50–03:50 (good, 3.0 h)	89.7° 06:55	4.74	20%	45.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2037-06-09&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.