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

2037-11-11astronomy score per night — click a bar for that night2037-12-10

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2037-11-11 Wed	100	—	unknown	18:40–04:05 (good, 9.42 h)	79.2° 22:30	10.85	23%	104.9°
2037-11-12 Thu	100	—	unknown	18:40–04:00 (good, 9.33 h)	79.2° 22:30	10.88	32%	93.2°
2037-11-13 Fri	100	—	unknown	18:40–03:55 (good, 9.25 h)	79.2° 22:25	10.91	42%	81.8°
2037-11-14 Sat	100	—	unknown	18:40–03:50 (good, 9.17 h)	79.2° 22:20	10.94	52%	70.8°
2037-11-15 Sun	100	—	unknown	18:40–03:50 (good, 9.17 h)	79.2° 22:15	10.97	61%	60.1°
2037-11-16 Mon	93	—	unknown	19:20–03:45 (good, 8.42 h)	79.2° 22:10	11.0	70%	49.9°
2037-11-17 Tue	85	—	unknown	00:10–03:40 (good, 3.5 h)	79.2° 22:10	11.02	78%	40.3°
2037-11-18 Wed	66	—	unknown	03:25–03:35 (good, 0.17 h)	79.2° 22:05	11.05	86%	31.9°
2037-11-19 Thu	40	—	unknown	18:35–03:45 (marginal, 9.17 h)	79.2° 22:00	11.08	92%	26.0°
2037-11-20 Fri	33	—	unknown	23:25–03:25 (marginal, 4.0 h)	79.2° 21:55	11.1	96%	24.5°
2037-11-21 Sat	31	—	unknown	18:35–21:25 (marginal, 2.83 h)	79.1° 21:50	11.13	99%	28.3°
2037-11-22 Sun	38	—	unknown	18:35–22:45 (marginal, 4.17 h)	79.2° 21:50	11.15	100%	36.0°
2037-11-23 Mon	54	—	unknown	18:35–02:15 (marginal, 7.67 h)	79.2° 21:45	11.18	99%	45.8°
2037-11-24 Tue	66	—	unknown	18:35–20:30 (good, 1.92 h)	79.2° 21:40	11.2	96%	56.7°
2037-11-25 Wed	99	—	unknown	18:35–23:15 (good, 4.67 h)	79.2° 21:35	11.22	91%	68.2°
2037-11-26 Thu	100	—	unknown	18:35–01:15 (good, 6.67 h)	79.2° 21:35	11.24	84%	80.2°
2037-11-27 Fri	100	—	unknown	18:35–02:35 (good, 8.0 h)	79.2° 21:30	11.26	75%	92.4°
2037-11-28 Sat	100	—	unknown	18:35–02:40 (good, 8.08 h)	79.2° 21:25	11.28	65%	104.8°
2037-11-29 Sun	100	—	unknown	18:35–02:45 (good, 8.17 h)	79.2° 21:20	11.3	54%	117.2°
2037-11-30 Mon	100	—	unknown	18:35–02:45 (good, 8.17 h)	79.2° 21:15	11.32	42%	129.4°
2037-12-01 Tue	100	—	unknown	18:35–02:45 (good, 8.17 h)	79.2° 21:15	11.34	31%	140.9°
2037-12-02 Wed	100	—	unknown	18:35–02:40 (good, 8.08 h)	79.2° 21:10	11.35	21%	150.5°
2037-12-03 Thu	100	—	unknown	18:35–02:40 (good, 8.08 h)	79.2° 21:05	11.37	12%	155.5°
2037-12-04 Fri	100	—	unknown	18:35–02:35 (good, 8.0 h)	79.2° 21:00	11.38	6%	153.1°
2037-12-05 Sat	100	—	unknown	18:35–02:30 (good, 7.92 h)	79.2° 20:55	11.4	2%	144.8°
2037-12-06 Sun	100	—	unknown	18:35–02:25 (good, 7.83 h)	79.2° 20:55	11.41	0%	133.8°
2037-12-07 Mon	100	—	unknown	18:35–02:20 (good, 7.75 h)	79.2° 20:50	11.42	1%	121.9°
2037-12-08 Tue	100	—	unknown	18:35–02:20 (good, 7.75 h)	79.2° 20:45	11.44	5%	109.8°
2037-12-09 Wed	100	—	unknown	18:35–02:15 (good, 7.67 h)	79.2° 20:40	11.45	10%	97.8°
2037-12-10 Thu	100	—	unknown	18:35–02:10 (good, 7.58 h)	79.2° 20:40	11.46	17%	86.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2037-11-11&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.