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: 07-31 (100), 08-01 (100), 08-02 (100), 08-03 (100), 08-04 (100) — by astronomy; check the weather when the night is within four days.

2033-07-31astronomy score per night — click a bar for that night2033-08-29

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-07-31 Sun	100	—	unknown	23:20–04:25 (good, 5.08 h)	89.7° 05:25	5.81	27%	143.6°
2033-08-01 Mon	100	—	unknown	23:20–04:25 (good, 5.08 h)	89.6° 05:20	5.86	36%	145.6°
2033-08-02 Tue	100	—	unknown	23:20–04:30 (good, 5.17 h)	89.5° 05:20	5.92	45%	144.1°
2033-08-03 Wed	100	—	unknown	23:15–04:30 (good, 5.25 h)	89.7° 05:15	5.98	55%	139.4°
2033-08-04 Thu	100	—	unknown	23:15–04:30 (good, 5.25 h)	89.8° 05:10	6.03	64%	132.3°
2033-08-05 Fri	100	—	unknown	23:10–04:30 (good, 5.33 h)	89.7° 05:05	6.09	74%	123.6°
2033-08-06 Sat	100	—	unknown	23:10–04:35 (good, 5.42 h)	89.6° 05:00	6.14	82%	113.8°
2033-08-07 Sun	100	—	unknown	23:15–04:35 (good, 5.33 h)	89.6° 05:00	6.2	90%	103.1°
2033-08-08 Mon	82	—	unknown	23:30–04:35 (good, 5.08 h)	89.7° 04:55	6.26	95%	91.8°
2033-08-09 Tue	73	—	unknown	00:55–04:40 (good, 3.75 h)	89.8° 04:50	6.32	99%	80.2°
2033-08-10 Wed	59	—	unknown	03:25–04:40 (good, 1.25 h)	89.7° 04:45	6.37	100%	68.5°
2033-08-11 Thu	45	—	unknown	22:20–04:40 (marginal, 6.33 h)	89.5° 04:40	6.43	98%	57.2°
2033-08-12 Fri	37	—	unknown	22:15–04:45 (marginal, 6.5 h)	89.6° 04:40	6.49	93%	46.9°
2033-08-13 Sat	40	—	unknown	22:10–04:45 (marginal, 6.58 h)	89.7° 04:35	6.54	86%	38.9°
2033-08-14 Sun	62	—	unknown	22:25–22:40 (good, 0.25 h)	89.7° 04:30	6.6	77%	34.8°
2033-08-15 Mon	82	—	unknown	22:25–02:35 (good, 4.17 h)	89.6° 04:25	6.66	66%	35.7°
2033-08-16 Tue	87	—	unknown	22:20–04:50 (good, 6.5 h)	89.5° 04:25	6.72	55%	41.1°
2033-08-17 Wed	93	—	unknown	22:15–04:50 (good, 6.58 h)	89.7° 04:20	6.78	44%	49.3°
2033-08-18 Thu	99	—	unknown	22:10–04:50 (good, 6.67 h)	89.8° 04:15	6.83	34%	59.0°
2033-08-19 Fri	100	—	unknown	22:05–04:55 (good, 6.83 h)	89.7° 04:10	6.89	24%	69.3°
2033-08-20 Sat	100	—	unknown	22:05–04:55 (good, 6.83 h)	89.6° 04:05	6.95	16%	79.9°
2033-08-21 Sun	100	—	unknown	22:00–04:55 (good, 6.92 h)	89.6° 04:05	7.0	9%	90.4°
2033-08-22 Mon	100	—	unknown	21:55–05:00 (good, 7.08 h)	89.7° 04:00	7.06	4%	100.8°
2033-08-23 Tue	100	—	unknown	21:55–05:00 (good, 7.08 h)	89.8° 03:55	7.12	1%	110.8°
2033-08-24 Wed	100	—	unknown	21:50–05:00 (good, 7.17 h)	89.7° 03:50	7.18	0%	120.4°
2033-08-25 Thu	100	—	unknown	21:50–05:05 (good, 7.25 h)	89.5° 03:45	7.23	1%	129.1°
2033-08-26 Fri	100	—	unknown	21:45–05:05 (good, 7.33 h)	89.6° 03:45	7.29	4%	136.6°
2033-08-27 Sat	100	—	unknown	21:45–05:05 (good, 7.33 h)	89.7° 03:40	7.35	8%	142.3°
2033-08-28 Sun	100	—	unknown	21:45–05:05 (good, 7.33 h)	89.7° 03:35	7.4	14%	145.2°
2033-08-29 Mon	100	—	unknown	21:40–05:10 (good, 7.5 h)	89.6° 03:30	7.46	21%	144.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-07-31&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.