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: 07-14 (92), 07-13 (90), 07-12 (88), 07-11 (87), 07-10 (85) — by astronomy; check the weather when the night is within four days.

2035-06-15astronomy score per night — click a bar for that night2035-07-14

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-06-15 Fri	35	—	unknown	02:30–03:40 (good, 1.17 h)	89.6° 08:30	4.46	79%	142.6°
2035-06-16 Sat	33	—	unknown	02:30–03:40 (good, 1.17 h)	89.8° 08:25	4.44	87%	139.5°
2035-06-17 Sun	33	—	unknown	02:25–03:40 (good, 1.25 h)	89.7° 08:20	4.44	92%	133.9°
2035-06-18 Mon	33	—	unknown	02:25–03:40 (good, 1.25 h)	89.6° 08:15	4.43	97%	126.7°
2035-06-19 Tue	33	—	unknown	02:20–03:40 (good, 1.33 h)	89.5° 08:15	4.43	99%	118.5°
2035-06-20 Wed	31	—	unknown	02:25–03:40 (good, 1.25 h)	89.7° 08:10	4.42	100%	109.6°
2035-06-21 Thu	28	—	unknown	02:30–03:40 (good, 1.17 h)	89.8° 08:05	4.42	99%	100.4°
2035-06-22 Fri	25	—	unknown	02:40–03:40 (good, 1.0 h)	89.7° 08:00	4.42	96%	90.9°
2035-06-23 Sat	24	—	unknown	03:15–03:40 (good, 0.42 h)	89.6° 07:55	4.43	91%	81.4°
2035-06-24 Sun	23	—	unknown	01:20–03:40 (marginal, 2.33 h)	89.6° 07:55	4.43	85%	71.9°
2035-06-25 Mon	23	—	unknown	01:15–03:40 (marginal, 2.42 h)	89.7° 07:50	4.44	78%	62.7°
2035-06-26 Tue	25	—	unknown	03:25–03:40 (good, 0.25 h)	89.8° 07:45	4.45	69%	53.9°
2035-06-27 Wed	29	—	unknown	02:10–03:40 (good, 1.5 h)	89.7° 07:40	4.47	59%	46.1°
2035-06-28 Thu	35	—	unknown	01:55–03:40 (good, 1.75 h)	89.5° 07:35	4.48	48%	40.2°
2035-06-29 Fri	46	—	unknown	01:30–03:40 (good, 2.17 h)	89.6° 07:35	4.5	38%	37.3°
2035-06-30 Sat	53	—	unknown	01:25–03:45 (good, 2.33 h)	89.7° 07:30	4.51	27%	38.6°
2035-07-01 Sun	61	—	unknown	01:20–03:45 (good, 2.42 h)	89.7° 07:25	4.53	17%	44.0°
2035-07-02 Mon	65	—	unknown	01:20–03:45 (good, 2.42 h)	89.6° 07:20	4.56	9%	52.5°
2035-07-03 Tue	67	—	unknown	01:15–03:45 (good, 2.5 h)	89.5° 07:20	4.58	4%	62.9°
2035-07-04 Wed	70	—	unknown	01:10–03:45 (good, 2.58 h)	89.7° 07:15	4.61	0%	74.4°
2035-07-05 Thu	71	—	unknown	01:05–03:45 (good, 2.67 h)	89.8° 07:10	4.63	0%	86.4°
2035-07-06 Fri	75	—	unknown	01:00–03:50 (good, 2.83 h)	89.7° 07:05	4.66	4%	98.3°
2035-07-07 Sat	77	—	unknown	01:00–03:50 (good, 2.83 h)	89.6° 07:00	4.69	9%	109.8°
2035-07-08 Sun	79	—	unknown	00:55–03:50 (good, 2.92 h)	89.6° 07:00	4.73	17%	120.4°
2035-07-09 Mon	81	—	unknown	00:50–03:50 (good, 3.0 h)	89.7° 06:55	4.76	26%	129.6°
2035-07-10 Tue	85	—	unknown	00:45–03:55 (good, 3.17 h)	89.8° 06:50	4.79	36%	136.9°
2035-07-11 Wed	87	—	unknown	00:45–03:55 (good, 3.17 h)	89.7° 06:45	4.83	46%	141.5°
2035-07-12 Thu	88	—	unknown	00:45–03:55 (good, 3.17 h)	89.5° 06:40	4.87	56%	142.6°
2035-07-13 Fri	90	—	unknown	00:40–03:55 (good, 3.25 h)	89.6° 06:40	4.91	66%	140.4°
2035-07-14 Sat	92	—	unknown	00:40–04:00 (good, 3.33 h)	89.7° 06:35	4.95	75%	135.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-06-15&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.