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: 06-27 (37), 06-15 (35), 06-14 (34), 06-12 (33), 06-13 (33) — by astronomy; check the weather when the night is within four days.

2046-05-29astronomy score per night — click a bar for that night2046-06-27

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-05-29 Tue	12	—	unknown	03:45–03:50 (good, 0.08 h)	89.8° 09:35	4.9	30%	37.3°
2046-05-30 Wed	13	—	unknown	03:35–03:45 (good, 0.17 h)	89.8° 09:30	4.86	21%	31.1°
2046-05-31 Thu	16	—	unknown	03:25–03:45 (good, 0.33 h)	89.6° 09:25	4.83	14%	28.3°
2046-06-01 Fri	19	—	unknown	03:20–03:45 (good, 0.42 h)	89.5° 09:25	4.79	8%	30.2°
2046-06-02 Sat	21	—	unknown	03:15–03:45 (good, 0.5 h)	89.7° 09:20	4.75	3%	36.2°
2046-06-03 Sun	22	—	unknown	03:10–03:45 (good, 0.58 h)	89.8° 09:15	4.72	1%	45.0°
2046-06-04 Mon	23	—	unknown	03:05–03:45 (good, 0.67 h)	89.8° 09:10	4.69	0%	55.2°
2046-06-05 Tue	24	—	unknown	03:05–03:40 (good, 0.58 h)	89.6° 09:05	4.66	2%	66.5°
2046-06-06 Wed	25	—	unknown	03:00–03:40 (good, 0.67 h)	89.6° 09:05	4.63	6%	78.3°
2046-06-07 Thu	26	—	unknown	02:55–03:40 (good, 0.75 h)	89.8° 09:00	4.6	12%	90.4°
2046-06-08 Fri	27	—	unknown	02:50–03:40 (good, 0.83 h)	89.8° 08:55	4.58	21%	102.7°
2046-06-09 Sat	28	—	unknown	02:45–03:40 (good, 0.92 h)	89.7° 08:50	4.55	31%	114.9°
2046-06-10 Sun	30	—	unknown	02:45–03:40 (good, 0.92 h)	89.5° 08:45	4.53	42%	126.7°
2046-06-11 Mon	31	—	unknown	02:40–03:40 (good, 1.0 h)	89.7° 08:45	4.51	53%	137.5°
2046-06-12 Tue	33	—	unknown	02:35–03:40 (good, 1.08 h)	89.8° 08:40	4.49	65%	146.4°
2046-06-13 Wed	33	—	unknown	02:30–03:40 (good, 1.17 h)	89.8° 08:35	4.48	75%	151.4°
2046-06-14 Thu	34	—	unknown	02:35–03:40 (good, 1.08 h)	89.6° 08:30	4.46	84%	150.4°
2046-06-15 Fri	35	—	unknown	02:30–03:40 (good, 1.17 h)	89.5° 08:30	4.45	92%	144.0°
2046-06-16 Sat	32	—	unknown	02:30–03:40 (good, 1.17 h)	89.7° 08:25	4.44	97%	134.6°
2046-06-17 Sun	32	—	unknown	02:25–03:40 (good, 1.25 h)	89.8° 08:20	4.43	99%	123.8°
2046-06-18 Mon	30	—	unknown	02:30–03:40 (good, 1.17 h)	89.8° 08:15	4.43	100%	112.5°
2046-06-19 Tue	27	—	unknown	02:30–03:40 (good, 1.17 h)	89.6° 08:10	4.42	98%	101.1°
2046-06-20 Wed	25	—	unknown	02:35–03:40 (good, 1.08 h)	89.6° 08:10	4.42	94%	89.8°
2046-06-21 Thu	23	—	unknown	03:20–03:40 (good, 0.33 h)	89.8° 08:05	4.42	88%	78.8°
2046-06-22 Fri	21	—	unknown	01:25–03:40 (marginal, 2.25 h)	89.8° 08:00	4.43	81%	68.1°
2046-06-23 Sat	22	—	unknown	01:20–03:40 (marginal, 2.33 h)	89.7° 07:55	4.43	73%	57.9°
2046-06-24 Sun	23	—	unknown	01:15–03:40 (marginal, 2.42 h)	89.5° 07:50	4.44	64%	48.3°
2046-06-25 Mon	26	—	unknown	02:35–03:40 (good, 1.08 h)	89.7° 07:50	4.45	55%	39.7°
2046-06-26 Tue	31	—	unknown	02:05–03:40 (good, 1.58 h)	89.8° 07:45	4.46	45%	32.7°
2046-06-27 Wed	37	—	unknown	01:55–03:40 (good, 1.75 h)	89.8° 07:40	4.47	36%	28.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-05-29&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.