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: 07-11 (87), 07-10 (85), 07-09 (81), 07-08 (79), 07-07 (77) — by astronomy; check the weather when the night is within four days.

2043-06-12astronomy score per night — click a bar for that night2043-07-11

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-06-12 Fri	32	—	unknown	02:35–03:40 (good, 1.08 h)	89.8° 08:40	4.5	35%	118.1°
2043-06-13 Sat	33	—	unknown	02:35–03:40 (good, 1.08 h)	89.7° 08:35	4.48	45%	128.1°
2043-06-14 Sun	35	—	unknown	02:30–03:40 (good, 1.17 h)	89.5° 08:35	4.47	55%	136.9°
2043-06-15 Mon	36	—	unknown	02:25–03:40 (good, 1.25 h)	89.7° 08:30	4.45	64%	143.8°
2043-06-16 Tue	37	—	unknown	02:25–03:40 (good, 1.25 h)	89.8° 08:25	4.44	73%	148.0°
2043-06-17 Wed	38	—	unknown	02:25–03:40 (good, 1.25 h)	89.8° 08:20	4.43	81%	148.4°
2043-06-18 Thu	39	—	unknown	02:20–03:40 (good, 1.33 h)	89.6° 08:15	4.43	88%	145.0°
2043-06-19 Fri	37	—	unknown	02:20–03:40 (good, 1.33 h)	89.6° 08:15	4.42	93%	138.8°
2043-06-20 Sat	37	—	unknown	02:15–03:40 (good, 1.42 h)	89.7° 08:10	4.42	97%	130.7°
2043-06-21 Sun	37	—	unknown	02:10–03:40 (good, 1.5 h)	89.8° 08:05	4.42	99%	121.5°
2043-06-22 Mon	34	—	unknown	02:15–03:40 (good, 1.42 h)	89.7° 08:00	4.42	100%	111.6°
2043-06-23 Tue	32	—	unknown	02:15–03:40 (good, 1.42 h)	89.6° 07:55	4.43	98%	101.3°
2043-06-24 Wed	29	—	unknown	02:20–03:40 (good, 1.33 h)	89.6° 07:55	4.43	94%	90.6°
2043-06-25 Thu	27	—	unknown	02:45–03:40 (good, 0.92 h)	89.8° 07:50	4.44	89%	79.8°
2043-06-26 Fri	26	—	unknown	03:15–03:40 (good, 0.42 h)	89.8° 07:45	4.45	82%	68.9°
2043-06-27 Sat	26	—	unknown	03:25–03:40 (good, 0.25 h)	89.7° 07:40	4.47	73%	58.3°
2043-06-28 Sun	28	—	unknown	02:40–03:40 (good, 1.0 h)	89.5° 07:40	4.48	63%	48.1°
2043-06-29 Mon	32	—	unknown	01:55–03:40 (good, 1.75 h)	89.7° 07:35	4.5	52%	39.2°
2043-06-30 Tue	39	—	unknown	01:45–03:45 (good, 2.0 h)	89.8° 07:30	4.51	41%	32.9°
2043-07-01 Wed	49	—	unknown	01:20–03:45 (good, 2.42 h)	89.8° 07:25	4.53	30%	31.3°
2043-07-02 Thu	56	—	unknown	01:20–03:45 (good, 2.42 h)	89.6° 07:20	4.56	20%	35.4°
2043-07-03 Fri	63	—	unknown	01:15–03:45 (good, 2.5 h)	89.6° 07:20	4.58	11%	43.7°
2043-07-04 Sat	70	—	unknown	01:10–03:45 (good, 2.58 h)	89.7° 07:15	4.61	5%	54.4°
2043-07-05 Sun	71	—	unknown	01:05–03:45 (good, 2.67 h)	89.8° 07:10	4.63	1%	66.3°
2043-07-06 Mon	75	—	unknown	01:00–03:50 (good, 2.83 h)	89.7° 07:05	4.66	0%	78.6°
2043-07-07 Tue	77	—	unknown	01:00–03:50 (good, 2.83 h)	89.6° 07:00	4.69	2%	90.9°
2043-07-08 Wed	79	—	unknown	00:55–03:50 (good, 2.92 h)	89.6° 07:00	4.73	6%	102.8°
2043-07-09 Thu	81	—	unknown	00:50–03:50 (good, 3.0 h)	89.8° 06:55	4.76	13%	114.2°
2043-07-10 Fri	85	—	unknown	00:45–03:55 (good, 3.17 h)	89.8° 06:50	4.8	21%	124.8°
2043-07-11 Sat	87	—	unknown	00:40–03:55 (good, 3.25 h)	89.7° 06:45	4.83	30%	134.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-06-12&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.