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: 11-25 (100), 11-26 (100), 11-27 (100), 11-28 (100), 11-29 (100) — by astronomy; check the weather when the night is within four days.

2037-11-23astronomy score per night — click a bar for that night2037-12-22

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2037-11-23 Mon	77	—	unknown	18:35–22:10 (good, 3.58 h)	87.2° 17:10	11.18	99%	94.9°
2037-11-24 Tue	85	—	unknown	18:35–22:55 (good, 4.33 h)	87.2° 17:05	11.2	96%	100.9°
2037-11-25 Wed	100	—	unknown	18:35–23:00 (good, 4.42 h)	87.2° 17:00	11.22	91%	106.5°
2037-11-26 Thu	100	—	unknown	18:35–23:00 (good, 4.42 h)	87.2° 17:00	11.24	84%	111.5°
2037-11-27 Fri	100	—	unknown	18:35–23:05 (good, 4.5 h)	87.2° 16:55	11.26	75%	115.4°
2037-11-28 Sat	100	—	unknown	18:35–23:05 (good, 4.5 h)	87.2° 16:50	11.28	65%	117.9°
2037-11-29 Sun	100	—	unknown	18:35–23:05 (good, 4.5 h)	87.2° 16:45	11.3	54%	118.8°
2037-11-30 Mon	100	—	unknown	18:35–23:00 (good, 4.42 h)	87.2° 16:40	11.32	42%	117.8°
2037-12-01 Tue	100	—	unknown	18:35–23:00 (good, 4.42 h)	87.2° 16:40	11.34	31%	115.0°
2037-12-02 Wed	100	—	unknown	18:35–22:55 (good, 4.33 h)	87.2° 16:35	11.35	21%	110.6°
2037-12-03 Thu	100	—	unknown	18:35–22:50 (good, 4.25 h)	87.2° 16:30	11.37	12%	104.9°
2037-12-04 Fri	100	—	unknown	18:35–22:45 (good, 4.17 h)	87.2° 16:25	11.38	6%	98.5°
2037-12-05 Sat	100	—	unknown	18:35–22:40 (good, 4.08 h)	87.2° 16:20	11.4	2%	91.7°
2037-12-06 Sun	100	—	unknown	18:35–22:40 (good, 4.08 h)	87.2° 16:20	11.41	0%	84.8°
2037-12-07 Mon	100	—	unknown	18:35–22:35 (good, 4.0 h)	87.2° 16:15	11.42	1%	78.4°
2037-12-08 Tue	100	—	unknown	18:35–22:30 (good, 3.92 h)	87.2° 16:10	11.44	5%	72.6°
2037-12-09 Wed	97	—	unknown	18:35–22:25 (good, 3.83 h)	87.2° 16:05	11.45	10%	67.8°
2037-12-10 Thu	92	—	unknown	18:35–22:25 (good, 3.83 h)	87.2° 16:05	11.46	17%	64.3°
2037-12-11 Fri	83	—	unknown	18:35–22:20 (good, 3.75 h)	87.2° 16:00	11.47	25%	62.1°
2037-12-12 Sat	72	—	unknown	18:35–22:05 (good, 3.5 h)	87.2° 15:55	11.47	34%	61.3°
2037-12-13 Sun	62	—	unknown	18:35–21:50 (good, 3.25 h)	87.2° 15:50	11.48	44%	61.9°
2037-12-14 Mon	54	—	unknown	18:35–21:40 (good, 3.08 h)	87.2° 15:45	11.49	53%	63.8°
2037-12-15 Tue	47	—	unknown	18:35–21:05 (good, 2.5 h)	87.2° 15:45	11.49	62%	66.9°
2037-12-16 Wed	42	—	unknown	18:35–20:10 (good, 1.58 h)	87.2° 15:40	11.5	71%	70.9°
2037-12-17 Thu	39	—	unknown	18:35–19:45 (good, 1.17 h)	87.2° 15:35	11.5	79%	75.7°
2037-12-18 Fri	38	—	unknown	18:35–19:40 (good, 1.08 h)	87.2° 15:30	11.5	87%	81.1°
2037-12-19 Sat	39	—	unknown	18:35–19:50 (good, 1.25 h)	87.2° 15:25	11.51	93%	86.9°
2037-12-20 Sun	43	—	unknown	18:35–20:15 (good, 1.67 h)	87.2° 15:25	11.51	97%	93.0°
2037-12-21 Mon	46	—	unknown	18:35–20:50 (good, 2.25 h)	87.2° 15:20	11.51	100%	99.1°
2037-12-22 Tue	51	—	unknown	18:35–21:05 (good, 2.5 h)	87.2° 15:15	11.51	100%	104.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2037-11-23&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.