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: 10-01 (100), 10-02 (100), 10-03 (100), 10-04 (100), 10-05 (100) — by astronomy; check the weather when the night is within four days.

2037-10-01astronomy score per night — click a bar for that night2037-10-30

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2037-10-01 Thu	100	—	unknown	20:35–03:45 (good, 7.17 h)	87.2° 21:40	9.2	55%	104.0°
2037-10-02 Fri	100	—	unknown	20:35–03:45 (good, 7.17 h)	87.2° 21:35	9.24	45%	109.4°
2037-10-03 Sat	100	—	unknown	20:35–03:45 (good, 7.17 h)	87.2° 21:30	9.29	34%	114.0°
2037-10-04 Sun	100	—	unknown	20:30–03:45 (good, 7.25 h)	87.2° 21:25	9.34	24%	117.4°
2037-10-05 Mon	100	—	unknown	20:30–03:40 (good, 7.17 h)	87.2° 21:20	9.38	15%	119.1°
2037-10-06 Tue	100	—	unknown	20:30–03:40 (good, 7.17 h)	87.2° 21:20	9.43	7%	118.7°
2037-10-07 Wed	100	—	unknown	20:25–03:35 (good, 7.17 h)	87.2° 21:15	9.48	2%	116.2°
2037-10-08 Thu	100	—	unknown	20:25–03:30 (good, 7.08 h)	87.2° 21:10	9.52	0%	111.9°
2037-10-09 Fri	100	—	unknown	20:25–03:25 (good, 7.0 h)	87.2° 21:05	9.57	1%	106.1°
2037-10-10 Sat	100	—	unknown	20:20–03:25 (good, 7.08 h)	87.2° 21:00	9.61	5%	99.5°
2037-10-11 Sun	100	—	unknown	20:20–03:20 (good, 7.0 h)	87.2° 21:00	9.66	11%	92.5°
2037-10-12 Mon	100	—	unknown	20:20–03:15 (good, 6.92 h)	87.2° 20:55	9.7	20%	85.6°
2037-10-13 Tue	100	—	unknown	20:15–03:10 (good, 6.92 h)	87.2° 20:50	9.75	29%	79.2°
2037-10-14 Wed	100	—	unknown	20:15–03:05 (good, 6.83 h)	87.2° 20:45	9.79	39%	73.4°
2037-10-15 Thu	97	—	unknown	20:15–03:05 (good, 6.83 h)	87.2° 20:45	9.84	49%	68.6°
2037-10-16 Fri	91	—	unknown	20:15–03:00 (good, 6.75 h)	87.2° 20:40	9.88	59%	64.8°
2037-10-17 Sat	84	—	unknown	20:10–02:55 (good, 6.75 h)	87.2° 20:35	9.92	68%	62.2°
2037-10-18 Sun	67	—	unknown	20:10–02:20 (good, 6.17 h)	87.2° 20:30	9.96	77%	61.0°
2037-10-19 Mon	64	—	unknown	20:10–23:50 (good, 3.67 h)	87.2° 20:25	10.01	84%	61.1°
2037-10-20 Tue	63	—	unknown	20:05–21:05 (good, 1.0 h)	87.2° 20:25	10.05	90%	62.6°
2037-10-21 Wed	62	—	unknown	20:05–21:00 (good, 0.92 h)	87.2° 20:20	10.09	95%	65.3°
2037-10-22 Thu	64	—	unknown	20:05–21:30 (good, 1.42 h)	87.2° 20:15	10.13	98%	69.0°
2037-10-23 Fri	69	—	unknown	20:05–22:25 (good, 2.33 h)	87.2° 20:10	10.17	100%	73.6°
2037-10-24 Sat	74	—	unknown	20:00–23:20 (good, 3.33 h)	87.2° 20:05	10.21	99%	78.8°
2037-10-25 Sun	78	—	unknown	19:00–23:00 (good, 4.0 h)	87.2° 19:05	10.25	97%	84.6°
2037-10-26 Mon	100	—	unknown	19:00–23:50 (good, 4.83 h)	87.2° 19:00	10.29	93%	90.5°
2037-10-27 Tue	100	—	unknown	19:00–00:40 (good, 5.67 h)	87.2° 18:55	10.33	87%	96.6°
2037-10-28 Wed	100	—	unknown	18:55–00:50 (good, 5.92 h)	87.2° 18:50	10.37	79%	102.4°
2037-10-29 Thu	100	—	unknown	18:55–00:50 (good, 5.92 h)	87.2° 18:50	10.4	70%	107.9°
2037-10-30 Fri	100	—	unknown	18:55–00:55 (good, 6.0 h)	87.2° 18:45	10.44	60%	112.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2037-10-01&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.