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: 10-31 (100), 11-01 (100), 11-02 (100), 11-03 (100), 11-04 (100) — by astronomy; check the weather when the night is within four days.

2042-10-27astronomy score per night — click a bar for that night2042-11-25

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2042-10-27 Mon	54	—	unknown	19:00–19:25 (good, 0.42 h)	87.2° 18:55	10.32	99%	66.3°
2042-10-28 Tue	62	—	unknown	18:55–20:30 (good, 1.58 h)	87.2° 18:55	10.36	100%	71.7°
2042-10-29 Wed	73	—	unknown	18:55–22:00 (good, 3.08 h)	87.2° 18:50	10.4	98%	78.3°
2042-10-30 Thu	79	—	unknown	18:55–23:00 (good, 4.08 h)	87.2° 18:45	10.43	93%	85.4°
2042-10-31 Fri	100	—	unknown	18:55–00:05 (good, 5.17 h)	87.2° 18:40	10.47	86%	92.5°
2042-11-01 Sat	100	—	unknown	18:50–00:30 (good, 5.67 h)	87.2° 18:35	10.51	78%	99.4°
2042-11-02 Sun	100	—	unknown	18:50–00:35 (good, 5.75 h)	87.2° 18:35	10.54	68%	105.5°
2042-11-03 Mon	100	—	unknown	18:50–00:40 (good, 5.83 h)	87.2° 18:30	10.58	58%	110.8°
2042-11-04 Tue	100	—	unknown	18:50–00:40 (good, 5.83 h)	87.2° 18:25	10.61	47%	114.9°
2042-11-05 Wed	100	—	unknown	18:50–00:40 (good, 5.83 h)	87.2° 18:20	10.65	38%	117.8°
2042-11-06 Thu	100	—	unknown	18:45–00:40 (good, 5.92 h)	87.2° 18:15	10.68	28%	119.3°
2042-11-07 Fri	100	—	unknown	18:45–00:35 (good, 5.83 h)	87.2° 18:15	10.71	20%	119.4°
2042-11-08 Sat	100	—	unknown	18:45–00:30 (good, 5.75 h)	87.2° 18:10	10.75	13%	118.0°
2042-11-09 Sun	100	—	unknown	18:45–00:25 (good, 5.67 h)	87.2° 18:05	10.78	8%	115.4°
2042-11-10 Mon	100	—	unknown	18:45–00:20 (good, 5.58 h)	87.2° 18:00	10.81	3%	111.8°
2042-11-11 Tue	100	—	unknown	18:45–00:20 (good, 5.58 h)	87.2° 18:00	10.84	1%	107.3°
2042-11-12 Wed	100	—	unknown	18:40–00:15 (good, 5.58 h)	87.2° 17:55	10.87	0%	102.1°
2042-11-13 Thu	100	—	unknown	18:40–00:10 (good, 5.5 h)	87.2° 17:50	10.9	1%	96.4°
2042-11-14 Fri	100	—	unknown	18:40–00:05 (good, 5.42 h)	87.2° 17:45	10.93	4%	90.5°
2042-11-15 Sat	100	—	unknown	18:40–00:00 (good, 5.33 h)	87.2° 17:40	10.96	9%	84.4°
2042-11-16 Sun	100	—	unknown	18:40–00:00 (good, 5.33 h)	87.2° 17:40	10.99	15%	78.5°
2042-11-17 Mon	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.2° 17:35	11.02	23%	72.9°
2042-11-18 Tue	92	—	unknown	18:40–23:50 (good, 5.17 h)	87.2° 17:30	11.05	32%	68.0°
2042-11-19 Wed	84	—	unknown	18:35–23:45 (good, 5.17 h)	87.2° 17:25	11.07	43%	64.0°
2042-11-20 Thu	77	—	unknown	18:35–23:20 (good, 4.75 h)	87.2° 17:20	11.1	54%	61.4°
2042-11-21 Fri	65	—	unknown	18:35–23:05 (good, 4.5 h)	87.2° 17:20	11.12	64%	60.4°
2042-11-22 Sat	54	—	unknown	18:35–20:45 (good, 2.17 h)	87.2° 17:15	11.15	75%	61.4°
2042-11-23 Sun	46	—	unknown	18:35–19:05 (good, 0.5 h)	87.2° 17:10	11.17	84%	64.3°
2042-11-24 Mon	44	—	unknown	18:35–19:00 (good, 0.42 h)	87.2° 17:05	11.19	92%	69.0°
2042-11-25 Tue	47	—	unknown	18:35–19:50 (good, 1.25 h)	87.2° 17:05	11.22	97%	75.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2042-10-27&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.