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: 10-29 (100), 10-30 (100), 10-31 (100), 11-01 (100), 11-02 (100) — by astronomy; check the weather when the night is within four days.

2037-10-21astronomy score per night — click a bar for that night2037-11-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2037-10-21 Wed	82	—	unknown	05:40–06:10 (good, 0.5 h)	79.2° 00:55	10.09	95%	37.6°
2037-10-22 Thu	43	—	unknown	20:05–06:10 (marginal, 10.08 h)	79.2° 00:50	10.13	98%	29.8°
2037-10-23 Fri	36	—	unknown	20:05–23:40 (marginal, 3.58 h)	79.2° 00:45	10.17	100%	24.9°
2037-10-24 Sat	38	—	unknown	20:00–23:55 (marginal, 3.92 h)	79.1° 00:40	10.21	99%	25.0°
2037-10-25 Sun	44	—	unknown	19:00–23:45 (marginal, 4.75 h)	79.2° 23:40	10.25	97%	30.2°
2037-10-26 Mon	84	—	unknown	19:00–19:10 (good, 0.17 h)	79.2° 23:35	10.29	93%	38.5°
2037-10-27 Tue	89	—	unknown	19:00–21:50 (good, 2.83 h)	79.2° 23:30	10.33	87%	48.5°
2037-10-28 Wed	95	—	unknown	18:55–00:45 (good, 5.83 h)	79.2° 23:25	10.37	79%	59.4°
2037-10-29 Thu	100	—	unknown	18:55–03:05 (good, 8.17 h)	79.2° 23:25	10.4	70%	71.0°
2037-10-30 Fri	100	—	unknown	18:55–04:25 (good, 9.5 h)	79.2° 23:20	10.44	60%	82.9°
2037-10-31 Sat	100	—	unknown	18:55–04:30 (good, 9.58 h)	79.2° 23:15	10.48	50%	95.3°
2037-11-01 Sun	100	—	unknown	18:50–04:35 (good, 9.75 h)	79.2° 23:10	10.51	38%	107.8°
2037-11-02 Mon	100	—	unknown	18:50–04:35 (good, 9.75 h)	79.2° 23:05	10.55	28%	120.5°
2037-11-03 Tue	100	—	unknown	18:50–04:35 (good, 9.75 h)	79.2° 23:05	10.58	18%	132.9°
2037-11-04 Wed	100	—	unknown	18:50–04:30 (good, 9.67 h)	79.2° 23:00	10.62	10%	144.4°
2037-11-05 Thu	100	—	unknown	18:50–04:30 (good, 9.67 h)	79.2° 22:55	10.65	4%	153.1°
2037-11-06 Fri	100	—	unknown	18:45–04:25 (good, 9.67 h)	79.2° 22:50	10.69	1%	155.5°
2037-11-07 Sat	100	—	unknown	18:45–04:20 (good, 9.58 h)	79.1° 22:45	10.72	0%	150.2°
2037-11-08 Sun	100	—	unknown	18:45–04:15 (good, 9.5 h)	79.2° 22:45	10.75	3%	140.3°
2037-11-09 Mon	100	—	unknown	18:45–04:10 (good, 9.42 h)	79.2° 22:40	10.79	8%	128.8°
2037-11-10 Tue	100	—	unknown	18:45–04:10 (good, 9.42 h)	79.2° 22:35	10.82	15%	116.8°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2037-10-21&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.