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: 10-10 (100), 10-11 (100), 10-12 (100), 10-13 (100), 10-14 (100) — by astronomy; check the weather when the night is within four days.

2044-10-07astronomy score per night — click a bar for that night2044-11-05

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2044-10-07 Fri	65	—	unknown	20:25–21:30 (good, 1.08 h)	87.2° 21:15	9.49	99%	65.2°
2044-10-08 Sat	71	—	unknown	20:25–23:10 (good, 2.75 h)	87.2° 21:10	9.54	96%	71.0°
2044-10-09 Sun	78	—	unknown	20:25–00:40 (good, 4.25 h)	87.2° 21:05	9.58	90%	77.8°
2044-10-10 Mon	100	—	unknown	20:20–01:55 (good, 5.58 h)	87.2° 21:00	9.63	82%	85.2°
2044-10-11 Tue	100	—	unknown	20:20–02:50 (good, 6.5 h)	87.2° 21:00	9.67	72%	92.9°
2044-10-12 Wed	100	—	unknown	20:20–02:55 (good, 6.58 h)	87.2° 20:55	9.72	61%	100.4°
2044-10-13 Thu	100	—	unknown	20:15–03:00 (good, 6.75 h)	87.2° 20:50	9.76	50%	107.5°
2044-10-14 Fri	100	—	unknown	20:15–03:00 (good, 6.75 h)	87.2° 20:45	9.81	39%	113.7°
2044-10-15 Sat	100	—	unknown	20:15–03:00 (good, 6.75 h)	87.2° 20:40	9.85	28%	118.5°
2044-10-16 Sun	100	—	unknown	20:10–03:00 (good, 6.83 h)	87.2° 20:40	9.89	18%	121.7°
2044-10-17 Mon	100	—	unknown	20:10–02:55 (good, 6.75 h)	87.2° 20:35	9.93	11%	122.8°
2044-10-18 Tue	100	—	unknown	20:10–02:50 (good, 6.67 h)	87.2° 20:30	9.98	5%	121.8°
2044-10-19 Wed	100	—	unknown	20:10–02:45 (good, 6.58 h)	87.2° 20:25	10.02	1%	118.9°
2044-10-20 Thu	100	—	unknown	20:05–02:40 (good, 6.58 h)	87.2° 20:20	10.06	0%	114.5°
2044-10-21 Fri	100	—	unknown	20:05–02:40 (good, 6.58 h)	87.2° 20:20	10.1	1%	109.0°
2044-10-22 Sat	100	—	unknown	20:05–02:35 (good, 6.5 h)	87.2° 20:15	10.14	4%	102.8°
2044-10-23 Sun	100	—	unknown	20:05–02:30 (good, 6.42 h)	87.2° 20:10	10.18	9%	96.4°
2044-10-24 Mon	100	—	unknown	20:00–02:25 (good, 6.42 h)	87.2° 20:05	10.22	15%	89.8°
2044-10-25 Tue	100	—	unknown	20:00–02:25 (good, 6.42 h)	87.2° 20:05	10.26	23%	83.3°
2044-10-26 Wed	100	—	unknown	20:00–02:20 (good, 6.33 h)	87.2° 20:00	10.3	31%	77.1°
2044-10-27 Thu	99	—	unknown	19:55–02:15 (good, 6.33 h)	87.2° 19:55	10.34	40%	71.3°
2044-10-28 Fri	91	—	unknown	19:55–02:10 (good, 6.25 h)	87.2° 19:50	10.38	49%	66.2°
2044-10-29 Sat	83	—	unknown	19:55–02:05 (good, 6.17 h)	87.2° 19:45	10.41	59%	62.0°
2044-10-30 Sun	70	—	unknown	18:55–00:35 (good, 5.67 h)	87.2° 18:45	10.45	68%	58.9°
2044-10-31 Mon	63	—	unknown	18:55–22:10 (good, 3.25 h)	87.2° 18:40	10.49	77%	57.3°
2044-11-01 Tue	54	—	unknown	18:50–01:20 (marginal, 6.5 h)	87.2° 18:35	10.52	85%	57.4°
2044-11-02 Wed	48	—	unknown	18:50–01:05 (marginal, 6.25 h)	87.2° 18:30	10.56	92%	59.4°
2044-11-03 Thu	47	—	unknown	18:50–00:50 (marginal, 6.0 h)	87.2° 18:25	10.6	97%	63.3°
2044-11-04 Fri	51	—	unknown	18:50–19:20 (good, 0.5 h)	87.2° 18:25	10.63	99%	68.7°
2044-11-05 Sat	62	—	unknown	18:45–20:55 (good, 2.17 h)	87.2° 18:20	10.66	100%	75.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2044-10-07&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.