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: 09-08 (100), 09-09 (100), 09-10 (100), 09-11 (100), 09-12 (100) — by astronomy; check the weather when the night is within four days.

2034-09-08astronomy score per night — click a bar for that night2034-10-07

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-09-08 Fri	100	—	unknown	21:20–05:20 (good, 8.0 h)	89.6° 02:55	8.0	15%	94.8°
2034-09-09 Sat	100	—	unknown	21:20–05:25 (good, 8.08 h)	89.7° 02:50	8.05	8%	105.5°
2034-09-10 Sun	100	—	unknown	21:15–05:25 (good, 8.17 h)	89.8° 02:45	8.11	3%	115.8°
2034-09-11 Mon	100	—	unknown	21:15–05:25 (good, 8.17 h)	89.6° 02:40	8.16	1%	125.3°
2034-09-12 Tue	100	—	unknown	21:15–05:25 (good, 8.17 h)	89.5° 02:40	8.22	0%	133.5°
2034-09-13 Wed	100	—	unknown	21:10–05:30 (good, 8.33 h)	89.6° 02:35	8.27	2%	139.8°
2034-09-14 Thu	100	—	unknown	21:10–05:30 (good, 8.33 h)	89.8° 02:30	8.32	5%	143.3°
2034-09-15 Fri	100	—	unknown	21:10–05:30 (good, 8.33 h)	89.7° 02:25	8.38	10%	143.5°
2034-09-16 Sat	100	—	unknown	21:05–05:30 (good, 8.42 h)	89.6° 02:20	8.43	17%	140.4°
2034-09-17 Sun	100	—	unknown	21:05–05:35 (good, 8.5 h)	89.5° 02:20	8.48	24%	134.8°
2034-09-18 Mon	100	—	unknown	21:00–05:35 (good, 8.58 h)	89.7° 02:15	8.53	33%	127.5°
2034-09-19 Tue	100	—	unknown	21:00–05:35 (good, 8.58 h)	89.8° 02:10	8.58	42%	119.1°
2034-09-20 Wed	100	—	unknown	21:00–05:35 (good, 8.58 h)	89.7° 02:05	8.64	51%	110.0°
2034-09-21 Thu	100	—	unknown	20:55–05:35 (good, 8.67 h)	89.5° 02:00	8.69	61%	100.4°
2034-09-22 Fri	100	—	unknown	20:55–05:40 (good, 8.75 h)	89.6° 02:00	8.74	71%	90.4°
2034-09-23 Sat	100	—	unknown	20:50–05:40 (good, 8.83 h)	89.7° 01:55	8.79	79%	80.1°
2034-09-24 Sun	100	—	unknown	22:15–05:40 (good, 7.42 h)	89.8° 01:50	8.84	87%	69.7°
2034-09-25 Mon	96	—	unknown	02:15–05:40 (good, 3.42 h)	89.6° 01:45	8.89	94%	59.4°
2034-09-26 Tue	59	—	unknown	20:45–05:45 (marginal, 9.0 h)	89.5° 01:40	8.94	98%	49.8°
2034-09-27 Wed	49	—	unknown	20:45–05:45 (marginal, 9.0 h)	89.6° 01:40	8.99	100%	41.8°
2034-09-28 Thu	43	—	unknown	20:45–05:45 (marginal, 9.0 h)	89.8° 01:35	9.04	99%	36.9°
2034-09-29 Fri	52	—	unknown	20:40–05:45 (marginal, 9.08 h)	89.7° 01:30	9.09	95%	36.7°
2034-09-30 Sat	86	—	unknown	20:40–20:55 (good, 0.25 h)	89.6° 01:25	9.13	89%	41.4°
2034-10-01 Sun	92	—	unknown	20:40–00:30 (good, 3.83 h)	89.5° 01:25	9.18	80%	49.5°
2034-10-02 Mon	99	—	unknown	20:35–04:20 (good, 7.75 h)	89.7° 01:20	9.23	70%	59.4°
2034-10-03 Tue	100	—	unknown	20:35–05:50 (good, 9.25 h)	89.8° 01:15	9.28	59%	70.2°
2034-10-04 Wed	100	—	unknown	20:35–05:50 (good, 9.25 h)	89.7° 01:10	9.33	48%	81.2°
2034-10-05 Thu	100	—	unknown	20:30–05:55 (good, 9.42 h)	89.5° 01:05	9.37	37%	92.2°
2034-10-06 Fri	100	—	unknown	20:30–05:55 (good, 9.42 h)	89.6° 01:05	9.42	27%	103.0°
2034-10-07 Sat	100	—	unknown	20:30–05:55 (good, 9.42 h)	89.7° 01:00	9.47	18%	113.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-09-08&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.