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: 10-22 (100), 10-23 (100), 10-24 (100), 10-25 (100), 10-26 (100) — by astronomy; check the weather when the night is within four days.

2035-10-19astronomy score per night — click a bar for that night2035-11-17

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-10-19 Fri	84	—	unknown	20:10–20:40 (good, 0.5 h)	79.1° 01:05	9.98	90%	38.6°
2035-10-20 Sat	91	—	unknown	20:10–00:15 (good, 4.08 h)	79.1° 01:00	10.03	82%	50.4°
2035-10-21 Sun	97	—	unknown	20:05–03:55 (good, 7.83 h)	79.1° 00:55	10.07	72%	63.0°
2035-10-22 Mon	100	—	unknown	20:05–05:35 (good, 9.5 h)	79.1° 00:50	10.11	61%	75.8°
2035-10-23 Tue	100	—	unknown	20:05–06:05 (good, 10.0 h)	79.1° 00:50	10.15	50%	88.8°
2035-10-24 Wed	100	—	unknown	20:00–06:10 (good, 10.17 h)	79.1° 00:45	10.19	38%	101.6°
2035-10-25 Thu	100	—	unknown	20:00–06:10 (good, 10.17 h)	79.1° 00:40	10.23	28%	114.1°
2035-10-26 Fri	100	—	unknown	20:00–06:05 (good, 10.08 h)	79.1° 00:35	10.27	19%	126.1°
2035-10-27 Sat	100	—	unknown	20:00–05:05 (good, 10.08 h)	79.1° 00:35	10.31	11%	137.5°
2035-10-28 Sun	100	—	unknown	18:55–05:00 (good, 10.08 h)	79.1° 23:30	10.35	5%	147.3°
2035-10-29 Mon	100	—	unknown	18:55–04:55 (good, 10.0 h)	79.1° 23:25	10.38	2%	154.4°
2035-10-30 Tue	100	—	unknown	18:55–04:55 (good, 10.0 h)	79.1° 23:20	10.42	0%	156.1°
2035-10-31 Wed	100	—	unknown	18:55–04:50 (good, 9.92 h)	79.1° 23:15	10.46	1%	152.0°
2035-11-01 Thu	100	—	unknown	18:50–04:45 (good, 9.92 h)	79.1° 23:15	10.49	3%	144.1°
2035-11-02 Fri	100	—	unknown	18:50–04:40 (good, 9.83 h)	79.1° 23:10	10.53	8%	134.5°
2035-11-03 Sat	100	—	unknown	18:50–04:35 (good, 9.75 h)	79.1° 23:05	10.57	14%	124.3°
2035-11-04 Sun	100	—	unknown	18:50–04:35 (good, 9.75 h)	79.1° 23:00	10.6	21%	113.8°
2035-11-05 Mon	100	—	unknown	18:50–04:30 (good, 9.67 h)	79.1° 22:55	10.64	29%	103.1°
2035-11-06 Tue	100	—	unknown	18:45–04:25 (good, 9.67 h)	79.1° 22:55	10.67	38%	92.3°
2035-11-07 Wed	100	—	unknown	18:45–04:20 (good, 9.58 h)	79.1° 22:50	10.7	47%	81.4°
2035-11-08 Thu	100	—	unknown	18:45–04:20 (good, 9.58 h)	79.1° 22:45	10.74	56%	70.4°
2035-11-09 Fri	100	—	unknown	18:45–04:15 (good, 9.5 h)	79.1° 22:40	10.77	66%	59.4°
2035-11-10 Sat	92	—	unknown	22:00–04:10 (good, 6.17 h)	79.1° 22:40	10.8	75%	48.4°
2035-11-11 Sun	84	—	unknown	03:05–04:05 (good, 1.0 h)	79.1° 22:35	10.83	84%	37.9°
2035-11-12 Mon	49	—	unknown	18:40–04:30 (marginal, 9.83 h)	79.1° 22:30	10.86	91%	28.9°
2035-11-13 Tue	34	—	unknown	18:40–04:00 (marginal, 9.33 h)	79.1° 22:25	10.89	96%	23.9°
2035-11-14 Wed	32	—	unknown	18:40–21:40 (marginal, 3.0 h)	79.1° 22:20	10.92	99%	26.1°
2035-11-15 Thu	40	—	unknown	18:40–23:00 (marginal, 4.33 h)	79.1° 22:20	10.95	100%	34.5°
2035-11-16 Fri	58	—	unknown	18:40–03:20 (marginal, 8.67 h)	79.1° 22:15	10.98	97%	46.0°
2035-11-17 Sat	94	—	unknown	18:40–21:45 (good, 3.08 h)	79.2° 22:10	11.01	92%	58.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-10-19&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.