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 Triangulum Pinwheel: 12-03 (100), 12-04 (100), 12-05 (100), 12-06 (100), 12-07 (100) — by astronomy; check the weather when the night is within four days.

2031-12-03astronomy score per night — click a bar for that night2032-01-01

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2031-12-03 Wed	100	—	unknown	18:35–02:15 (good, 7.67 h)	79.1° 21:05	11.36	79%	94.7°
2031-12-04 Thu	100	—	unknown	18:35–02:20 (good, 7.75 h)	79.1° 21:05	11.38	70%	105.9°
2031-12-05 Fri	100	—	unknown	18:35–02:25 (good, 7.83 h)	79.1° 21:00	11.39	62%	117.1°
2031-12-06 Sat	100	—	unknown	18:35–02:20 (good, 7.75 h)	79.1° 20:55	11.4	52%	128.2°
2031-12-07 Sun	100	—	unknown	18:35–02:20 (good, 7.75 h)	79.1° 20:50	11.42	42%	139.3°
2031-12-08 Mon	100	—	unknown	18:35–02:15 (good, 7.67 h)	79.1° 20:45	11.43	33%	149.8°
2031-12-09 Tue	100	—	unknown	18:35–02:15 (good, 7.67 h)	79.1° 20:45	11.44	23%	158.6°
2031-12-10 Wed	100	—	unknown	18:35–02:10 (good, 7.58 h)	79.1° 20:40	11.45	15%	162.0°
2031-12-11 Thu	100	—	unknown	18:35–02:10 (good, 7.58 h)	79.1° 20:35	11.46	8%	156.7°
2031-12-12 Fri	100	—	unknown	18:35–02:05 (good, 7.5 h)	79.1° 20:30	11.47	3%	146.0°
2031-12-13 Sat	100	—	unknown	18:35–02:00 (good, 7.42 h)	79.1° 20:30	11.48	0%	133.2°
2031-12-14 Sun	100	—	unknown	18:35–01:55 (good, 7.33 h)	79.1° 20:25	11.48	0%	119.5°
2031-12-15 Mon	100	—	unknown	18:35–01:50 (good, 7.25 h)	79.1° 20:20	11.49	4%	105.4°
2031-12-16 Tue	100	—	unknown	18:35–01:50 (good, 7.25 h)	79.1° 20:15	11.5	10%	91.1°
2031-12-17 Wed	100	—	unknown	18:35–01:45 (good, 7.17 h)	79.1° 20:10	11.5	18%	77.1°
2031-12-18 Thu	100	—	unknown	18:35–01:40 (good, 7.08 h)	79.1° 20:10	11.5	27%	63.3°
2031-12-19 Fri	94	—	unknown	18:35–01:35 (good, 7.0 h)	79.1° 20:05	11.51	38%	50.1°
2031-12-20 Sat	86	—	unknown	18:35–01:30 (good, 6.92 h)	79.1° 20:00	11.51	49%	37.7°
2031-12-21 Sun	63	—	unknown	21:20–00:40 (good, 3.33 h)	79.1° 19:55	11.51	60%	26.8°
2031-12-22 Mon	49	—	unknown	18:35–01:50 (marginal, 7.25 h)	79.1° 19:50	11.51	70%	19.2°
2031-12-23 Tue	33	—	unknown	18:40–01:30 (marginal, 6.83 h)	79.1° 19:50	11.51	79%	18.9°
2031-12-24 Wed	25	—	unknown	18:40–01:05 (marginal, 6.42 h)	79.1° 19:45	11.5	87%	25.7°
2031-12-25 Thu	25	—	unknown	18:40–00:00 (marginal, 5.33 h)	79.1° 19:40	11.5	93%	35.5°
2031-12-26 Fri	33	—	unknown	18:40–00:45 (marginal, 6.08 h)	79.1° 19:35	11.5	97%	46.3°
2031-12-27 Sat	45	—	unknown	18:40–00:50 (marginal, 6.17 h)	79.1° 19:35	11.49	99%	57.6°
2031-12-28 Sun	62	—	unknown	18:40–20:15 (good, 1.58 h)	79.1° 19:30	11.49	100%	68.9°
2031-12-29 Mon	76	—	unknown	18:40–22:20 (good, 3.67 h)	79.1° 19:25	11.48	98%	80.2°
2031-12-30 Tue	100	—	unknown	18:40–23:35 (good, 4.92 h)	79.1° 19:20	11.47	96%	91.5°
2031-12-31 Wed	100	—	unknown	18:45–00:25 (good, 5.67 h)	79.1° 19:15	11.46	91%	102.7°
2032-01-01 Thu	100	—	unknown	18:45–00:30 (good, 5.75 h)	79.1° 19:15	11.45	85%	113.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2031-12-03&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.