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 North America Nebula: 11-21 (100), 11-22 (100), 11-23 (100), 11-24 (100), 11-25 (100) — by astronomy; check the weather when the night is within four days.

2035-11-21astronomy score per night — click a bar for that night2035-12-20

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-11-21 Wed	100	—	unknown	18:35–23:35 (good, 5.0 h)	87.2° 17:20	11.11	53%	121.9°
2035-11-22 Thu	100	—	unknown	18:35–23:35 (good, 5.0 h)	87.2° 17:15	11.14	42%	121.8°
2035-11-23 Fri	100	—	unknown	18:35–23:30 (good, 4.92 h)	87.2° 17:10	11.16	32%	119.7°
2035-11-24 Sat	100	—	unknown	18:35–23:30 (good, 4.92 h)	87.2° 17:05	11.19	22%	116.0°
2035-11-25 Sun	100	—	unknown	18:35–23:25 (good, 4.83 h)	87.2° 17:05	11.21	15%	111.1°
2035-11-26 Mon	100	—	unknown	18:35–23:20 (good, 4.75 h)	87.2° 17:00	11.23	8%	105.4°
2035-11-27 Tue	100	—	unknown	18:35–23:15 (good, 4.67 h)	87.2° 16:55	11.25	4%	99.2°
2035-11-28 Wed	100	—	unknown	18:35–23:10 (good, 4.58 h)	87.2° 16:50	11.27	1%	92.7°
2035-11-29 Thu	100	—	unknown	18:35–23:10 (good, 4.58 h)	87.2° 16:50	11.29	0%	86.2°
2035-11-30 Fri	100	—	unknown	18:35–23:05 (good, 4.5 h)	87.2° 16:45	11.31	1%	80.0°
2035-12-01 Sat	100	—	unknown	18:35–23:00 (good, 4.42 h)	87.2° 16:40	11.33	4%	74.1°
2035-12-02 Sun	100	—	unknown	18:35–22:55 (good, 4.33 h)	87.2° 16:35	11.34	9%	68.8°
2035-12-03 Mon	95	—	unknown	18:35–22:50 (good, 4.25 h)	87.2° 16:30	11.36	15%	64.4°
2035-12-04 Tue	92	—	unknown	18:35–22:50 (good, 4.25 h)	87.2° 16:30	11.38	22%	60.9°
2035-12-05 Wed	87	—	unknown	18:35–22:45 (good, 4.17 h)	87.2° 16:25	11.39	30%	58.8°
2035-12-06 Thu	75	—	unknown	18:35–22:25 (good, 3.83 h)	87.2° 16:20	11.4	39%	58.1°
2035-12-07 Fri	63	—	unknown	18:35–22:15 (good, 3.67 h)	87.2° 16:15	11.42	49%	58.9°
2035-12-08 Sat	54	—	unknown	18:35–22:00 (good, 3.42 h)	87.2° 16:10	11.43	59%	61.5°
2035-12-09 Sun	48	—	unknown	18:35–20:35 (good, 2.0 h)	87.2° 16:10	11.44	69%	65.5°
2035-12-10 Mon	43	—	unknown	18:35–19:55 (good, 1.33 h)	87.2° 16:05	11.45	78%	70.9°
2035-12-11 Tue	43	—	unknown	18:35–19:45 (good, 1.17 h)	87.2° 16:00	11.46	87%	77.4°
2035-12-12 Wed	45	—	unknown	18:35–20:05 (good, 1.5 h)	87.2° 15:55	11.47	93%	84.7°
2035-12-13 Thu	51	—	unknown	18:35–20:40 (good, 2.08 h)	87.2° 15:55	11.48	98%	92.5°
2035-12-14 Fri	58	—	unknown	18:35–21:25 (good, 2.83 h)	87.2° 15:50	11.48	100%	100.3°
2035-12-15 Sat	66	—	unknown	18:35–21:40 (good, 3.08 h)	87.2° 15:45	11.49	99%	107.7°
2035-12-16 Sun	81	—	unknown	18:35–21:45 (good, 3.17 h)	87.2° 15:40	11.5	94%	114.0°
2035-12-17 Mon	84	—	unknown	18:35–21:45 (good, 3.17 h)	87.2° 15:35	11.5	88%	118.7°
2035-12-18 Tue	85	—	unknown	18:35–21:45 (good, 3.17 h)	87.2° 15:35	11.5	79%	121.3°
2035-12-19 Wed	84	—	unknown	18:35–21:50 (good, 3.25 h)	87.2° 15:30	11.51	69%	121.8°
2035-12-20 Thu	82	—	unknown	18:35–21:45 (good, 3.17 h)	87.2° 15:25	11.51	58%	120.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-11-21&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.