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: 10-25 (100), 10-26 (100), 10-27 (100), 10-28 (100), 10-29 (100) — by astronomy; check the weather when the night is within four days.

2041-10-25astronomy score per night — click a bar for that night2041-11-23

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2041-10-25 Fri	100	—	unknown	20:00–06:10 (good, 10.17 h)	79.2° 00:40	10.25	1%	159.1°
2041-10-26 Sat	100	—	unknown	20:00–05:05 (good, 10.08 h)	79.2° 00:35	10.29	3%	152.2°
2041-10-27 Sun	100	—	unknown	19:00–05:05 (good, 10.08 h)	79.2° 23:30	10.33	8%	142.3°
2041-10-28 Mon	100	—	unknown	18:55–05:00 (good, 10.08 h)	79.2° 23:25	10.37	15%	130.9°
2041-10-29 Tue	100	—	unknown	18:55–04:55 (good, 10.0 h)	79.2° 23:25	10.4	23%	118.9°
2041-10-30 Wed	100	—	unknown	18:55–04:50 (good, 9.92 h)	79.2° 23:20	10.44	33%	106.4°
2041-10-31 Thu	100	—	unknown	18:55–04:50 (good, 9.92 h)	79.2° 23:15	10.48	44%	93.5°
2041-11-01 Fri	100	—	unknown	18:50–04:45 (good, 9.92 h)	79.2° 23:10	10.51	55%	80.4°
2041-11-02 Sat	100	—	unknown	18:50–04:40 (good, 9.83 h)	79.2° 23:05	10.55	66%	67.2°
2041-11-03 Sun	95	—	unknown	20:25–04:35 (good, 8.17 h)	79.2° 23:05	10.59	76%	53.9°
2041-11-04 Mon	86	—	unknown	03:15–04:30 (good, 1.25 h)	79.2° 23:00	10.62	86%	41.0°
2041-11-05 Tue	53	—	unknown	18:50–04:55 (marginal, 10.08 h)	79.2° 22:55	10.66	93%	29.2°
2041-11-06 Wed	32	—	unknown	00:30–04:25 (marginal, 3.92 h)	79.2° 22:50	10.69	98%	20.9°
2041-11-07 Thu	30	—	unknown	18:45–21:20 (marginal, 2.58 h)	79.2° 22:50	10.72	100%	20.8°
2041-11-08 Fri	33	—	unknown	18:45–22:00 (marginal, 3.25 h)	79.2° 22:45	10.76	99%	28.7°
2041-11-09 Sat	51	—	unknown	18:45–01:35 (marginal, 6.83 h)	79.2° 22:40	10.79	96%	39.8°
2041-11-10 Sun	63	—	unknown	18:45–20:55 (good, 2.17 h)	79.2° 22:35	10.82	91%	51.8°
2041-11-11 Mon	95	—	unknown	18:40–00:00 (good, 5.33 h)	79.2° 22:30	10.85	84%	63.9°
2041-11-12 Tue	100	—	unknown	18:40–02:15 (good, 7.58 h)	79.2° 22:30	10.88	76%	75.8°
2041-11-13 Wed	100	—	unknown	18:40–03:30 (good, 8.83 h)	79.2° 22:25	10.91	67%	87.5°
2041-11-14 Thu	100	—	unknown	18:40–03:35 (good, 8.92 h)	79.2° 22:20	10.94	57%	99.0°
2041-11-15 Fri	100	—	unknown	18:40–03:40 (good, 9.0 h)	79.2° 22:15	10.97	48%	110.2°
2041-11-16 Sat	100	—	unknown	18:40–03:40 (good, 9.0 h)	79.2° 22:10	11.0	38%	121.2°
2041-11-17 Sun	100	—	unknown	18:40–03:40 (good, 9.0 h)	79.2° 22:10	11.03	29%	131.9°
2041-11-18 Mon	100	—	unknown	18:35–03:35 (good, 9.0 h)	79.2° 22:05	11.05	21%	142.2°
2041-11-19 Tue	100	—	unknown	18:35–03:35 (good, 9.0 h)	79.2° 22:00	11.08	14%	151.6°
2041-11-20 Wed	100	—	unknown	18:35–03:30 (good, 8.92 h)	79.2° 21:55	11.1	8%	158.6°
2041-11-21 Thu	100	—	unknown	18:35–03:25 (good, 8.83 h)	79.2° 21:55	11.13	3%	160.1°
2041-11-22 Fri	100	—	unknown	18:35–03:20 (good, 8.75 h)	79.2° 21:50	11.15	1%	154.7°
2041-11-23 Sat	100	—	unknown	18:35–03:15 (good, 8.67 h)	79.2° 21:45	11.18	0%	145.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2041-10-25&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.