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: 06-17 (100), 06-18 (100), 06-19 (100), 06-20 (100), 06-21 (100) — by astronomy; check the weather when the night is within four days.

2047-06-11astronomy score per night — click a bar for that night2047-07-10

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-06-11 Tue	77	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 05:00	4.52	82%	59.6°
2047-06-12 Wed	85	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:55	4.5	73%	55.5°
2047-06-13 Thu	90	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 04:50	4.48	64%	53.5°
2047-06-14 Fri	93	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:50	4.47	54%	53.4°
2047-06-15 Sat	96	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:45	4.45	44%	55.2°
2047-06-16 Sun	99	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:40	4.44	35%	58.6°
2047-06-17 Mon	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:35	4.44	26%	63.4°
2047-06-18 Tue	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 04:35	4.43	18%	69.1°
2047-06-19 Wed	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:30	4.42	12%	75.5°
2047-06-20 Thu	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:25	4.42	6%	82.4°
2047-06-21 Fri	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:20	4.42	2%	89.7°
2047-06-22 Sat	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:15	4.42	0%	97.0°
2047-06-23 Sun	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:15	4.43	0%	104.3°
2047-06-24 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:10	4.44	2%	111.2°
2047-06-25 Tue	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:05	4.44	6%	117.4°
2047-06-26 Wed	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:00	4.45	13%	122.4°
2047-06-27 Thu	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 03:55	4.47	21%	125.7°
2047-06-28 Fri	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 03:55	4.48	30%	126.9°
2047-06-29 Sat	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 03:50	4.5	41%	125.6°
2047-06-30 Sun	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.2° 03:45	4.52	52%	122.0°
2047-07-01 Mon	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.2° 03:40	4.54	64%	116.4°
2047-07-02 Tue	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 03:40	4.56	74%	109.3°
2047-07-03 Wed	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.2° 03:35	4.58	84%	101.2°
2047-07-04 Thu	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.2° 03:30	4.61	92%	92.7°
2047-07-05 Fri	78	—	unknown	23:10–03:45 (good, 4.58 h)	87.2° 03:25	4.64	97%	84.0°
2047-07-06 Sat	67	—	unknown	23:10–03:50 (good, 4.67 h)	87.2° 03:20	4.67	100%	75.7°
2047-07-07 Sun	57	—	unknown	23:15–03:50 (good, 4.58 h)	87.2° 03:20	4.7	100%	68.1°
2047-07-08 Mon	53	—	unknown	23:15–01:05 (good, 1.83 h)	87.2° 03:15	4.73	97%	61.7°
2047-07-09 Tue	53	—	unknown	23:05–01:05 (good, 2.0 h)	87.2° 03:10	4.76	92%	56.9°
2047-07-10 Wed	59	—	unknown	23:05–01:45 (good, 2.67 h)	87.2° 03:05	4.8	86%	54.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-06-11&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.