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: 12-11 (100), 12-12 (100), 12-13 (100), 12-14 (100), 12-15 (100) — by astronomy; check the weather when the night is within four days.

2033-12-11astronomy score per night — click a bar for that night2034-01-09

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-12-11 Sun	100	—	unknown	18:35–01:55 (good, 7.33 h)	79.1° 20:35	11.47	66%	117.2°
2033-12-12 Mon	100	—	unknown	18:35–01:55 (good, 7.33 h)	79.1° 20:30	11.47	57%	128.3°
2033-12-13 Tue	100	—	unknown	18:35–01:55 (good, 7.33 h)	79.1° 20:25	11.48	47%	138.7°
2033-12-14 Wed	100	—	unknown	18:35–01:50 (good, 7.25 h)	79.1° 20:20	11.49	38%	148.1°
2033-12-15 Thu	100	—	unknown	18:35–01:50 (good, 7.25 h)	79.1° 20:20	11.49	29%	155.4°
2033-12-16 Fri	100	—	unknown	18:35–01:45 (good, 7.17 h)	79.1° 20:15	11.5	21%	158.6°
2033-12-17 Sat	100	—	unknown	18:35–01:40 (good, 7.08 h)	79.1° 20:10	11.5	14%	156.0°
2033-12-18 Sun	100	—	unknown	18:35–01:40 (good, 7.08 h)	79.1° 20:05	11.5	8%	148.8°
2033-12-19 Mon	100	—	unknown	18:35–01:35 (good, 7.0 h)	79.1° 20:00	11.51	4%	139.3°
2033-12-20 Tue	100	—	unknown	18:35–01:30 (good, 6.92 h)	79.1° 20:00	11.51	1%	128.6°
2033-12-21 Wed	100	—	unknown	18:35–01:25 (good, 6.83 h)	79.1° 19:55	11.51	0%	117.2°
2033-12-22 Thu	100	—	unknown	18:35–01:25 (good, 6.83 h)	79.1° 19:50	11.51	2%	105.3°
2033-12-23 Fri	100	—	unknown	18:40–01:20 (good, 6.67 h)	79.1° 19:45	11.5	5%	93.2°
2033-12-24 Sat	100	—	unknown	18:40–01:15 (good, 6.58 h)	79.1° 19:45	11.5	11%	80.8°
2033-12-25 Sun	100	—	unknown	18:40–01:10 (good, 6.5 h)	79.1° 19:40	11.5	18%	68.3°
2033-12-26 Mon	99	—	unknown	18:40–01:05 (good, 6.42 h)	79.1° 19:35	11.49	28%	55.9°
2033-12-27 Tue	90	—	unknown	18:40–01:05 (good, 6.42 h)	79.1° 19:30	11.49	38%	43.8°
2033-12-28 Wed	81	—	unknown	18:40–01:00 (good, 6.33 h)	79.1° 19:25	11.48	49%	32.6°
2033-12-29 Thu	60	—	unknown	21:30–22:15 (good, 0.75 h)	79.1° 19:25	11.48	60%	24.0°
2033-12-30 Fri	41	—	unknown	18:40–01:10 (marginal, 6.5 h)	79.1° 19:20	11.47	71%	21.7°
2033-12-31 Sat	28	—	unknown	18:45–00:50 (marginal, 6.08 h)	79.1° 19:15	11.46	81%	27.5°
2034-01-01 Sun	26	—	unknown	18:45–00:30 (marginal, 5.75 h)	79.1° 19:10	11.45	89%	37.9°
2034-01-02 Mon	33	—	unknown	18:45–00:25 (marginal, 5.67 h)	79.1° 19:05	11.44	95%	50.0°
2034-01-03 Tue	46	—	unknown	18:45–00:30 (marginal, 5.75 h)	79.1° 19:05	11.43	99%	62.7°
2034-01-04 Wed	63	—	unknown	18:45–21:20 (good, 2.58 h)	79.1° 19:00	11.41	100%	75.6°
2034-01-05 Thu	79	—	unknown	18:45–22:45 (good, 4.0 h)	79.1° 18:55	11.4	98%	88.3°
2034-01-06 Fri	100	—	unknown	18:50–23:55 (good, 5.08 h)	79.1° 18:50	11.39	95%	100.7°
2034-01-07 Sat	100	—	unknown	18:50–00:05 (good, 5.25 h)	79.1° 18:50	11.37	89%	112.7°
2034-01-08 Sun	100	—	unknown	18:50–00:05 (good, 5.25 h)	79.1° 18:45	11.36	82%	124.2°
2034-01-09 Mon	100	—	unknown	18:50–00:05 (good, 5.25 h)	79.1° 18:40	11.34	74%	135.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-12-11&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.