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: 10-04 (100), 10-05 (100), 10-06 (100), 10-07 (100), 10-08 (100) — by astronomy; check the weather when the night is within four days.

2042-10-04astronomy score per night — click a bar for that night2042-11-02

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2042-10-04 Sat	100	—	unknown	20:35–03:25 (good, 6.83 h)	87.2° 21:25	9.33	63%	95.1°
2042-10-05 Sun	100	—	unknown	20:30–03:30 (good, 7.0 h)	87.2° 21:25	9.38	52%	101.5°
2042-10-06 Mon	100	—	unknown	20:30–03:30 (good, 7.0 h)	87.2° 21:20	9.42	41%	107.2°
2042-10-07 Tue	100	—	unknown	20:25–03:30 (good, 7.08 h)	87.2° 21:15	9.47	32%	112.0°
2042-10-08 Wed	100	—	unknown	20:25–03:30 (good, 7.08 h)	87.2° 21:10	9.51	23%	115.8°
2042-10-09 Thu	100	—	unknown	20:25–03:30 (good, 7.08 h)	87.2° 21:05	9.56	15%	118.3°
2042-10-10 Fri	100	—	unknown	20:25–03:25 (good, 7.0 h)	87.2° 21:05	9.61	9%	119.4°
2042-10-11 Sat	100	—	unknown	20:20–03:20 (good, 7.0 h)	87.2° 21:00	9.65	4%	119.1°
2042-10-12 Sun	100	—	unknown	20:20–03:15 (good, 6.92 h)	87.2° 20:55	9.69	1%	117.4°
2042-10-13 Mon	100	—	unknown	20:20–03:10 (good, 6.83 h)	87.2° 20:50	9.74	0%	114.6°
2042-10-14 Tue	100	—	unknown	20:15–03:10 (good, 6.92 h)	87.2° 20:50	9.78	1%	110.7°
2042-10-15 Wed	100	—	unknown	20:15–03:05 (good, 6.83 h)	87.2° 20:45	9.83	3%	106.0°
2042-10-16 Thu	100	—	unknown	20:15–03:00 (good, 6.75 h)	87.2° 20:40	9.87	7%	100.7°
2042-10-17 Fri	100	—	unknown	20:10–02:55 (good, 6.75 h)	87.2° 20:35	9.91	13%	95.0°
2042-10-18 Sat	100	—	unknown	20:10–02:50 (good, 6.67 h)	87.2° 20:30	9.95	20%	89.1°
2042-10-19 Sun	100	—	unknown	20:10–02:50 (good, 6.67 h)	87.2° 20:30	10.0	28%	83.1°
2042-10-20 Mon	100	—	unknown	20:05–02:45 (good, 6.67 h)	87.2° 20:25	10.04	38%	77.2°
2042-10-21 Tue	98	—	unknown	20:05–02:40 (good, 6.58 h)	87.2° 20:20	10.08	48%	71.8°
2042-10-22 Wed	89	—	unknown	20:05–02:35 (good, 6.5 h)	87.2° 20:15	10.12	58%	67.0°
2042-10-23 Thu	81	—	unknown	20:05–02:35 (good, 6.5 h)	87.2° 20:10	10.16	69%	63.2°
2042-10-24 Fri	66	—	unknown	20:00–00:45 (good, 4.75 h)	87.2° 20:10	10.2	79%	61.0°
2042-10-25 Sat	61	—	unknown	20:00–20:35 (good, 0.58 h)	87.2° 20:05	10.24	88%	60.6°
2042-10-26 Sun	55	—	unknown	19:00–19:05 (good, 0.08 h)	87.2° 19:00	10.28	94%	62.4°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2042-10-04&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.