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.

2043-10-25astronomy score per night — click a bar for that night2043-11-23

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-10-25 Sun	100	—	unknown	19:00–05:00 (good, 10.0 h)	79.2° 23:40	10.23	41%	97.6°
2043-10-26 Mon	100	—	unknown	19:00–05:05 (good, 10.08 h)	79.2° 23:35	10.27	31%	110.2°
2043-10-27 Tue	100	—	unknown	19:00–05:05 (good, 10.08 h)	79.2° 23:35	10.31	22%	122.5°
2043-10-28 Wed	100	—	unknown	18:55–05:00 (good, 10.08 h)	79.2° 23:30	10.35	14%	134.4°
2043-10-29 Thu	100	—	unknown	18:55–04:55 (good, 10.0 h)	79.2° 23:25	10.39	8%	145.6°
2043-10-30 Fri	100	—	unknown	18:55–04:55 (good, 10.0 h)	79.2° 23:20	10.42	3%	155.5°
2043-10-31 Sat	100	—	unknown	18:55–04:50 (good, 9.92 h)	79.2° 23:15	10.46	1%	162.5°
2043-11-01 Sun	100	—	unknown	18:50–04:45 (good, 9.92 h)	79.2° 23:15	10.5	0%	162.6°
2043-11-02 Mon	100	—	unknown	18:50–04:40 (good, 9.83 h)	79.2° 23:10	10.53	1%	156.0°
2043-11-03 Tue	100	—	unknown	18:50–04:40 (good, 9.83 h)	79.2° 23:05	10.57	4%	146.5°
2043-11-04 Wed	100	—	unknown	18:50–04:35 (good, 9.75 h)	79.2° 23:00	10.6	8%	136.0°
2043-11-05 Thu	100	—	unknown	18:50–04:30 (good, 9.67 h)	79.2° 22:55	10.64	14%	125.0°
2043-11-06 Fri	100	—	unknown	18:45–04:25 (good, 9.67 h)	79.2° 22:55	10.67	22%	113.8°
2043-11-07 Sat	100	—	unknown	18:45–04:20 (good, 9.58 h)	79.2° 22:50	10.71	30%	102.4°
2043-11-08 Sun	100	—	unknown	18:45–04:20 (good, 9.58 h)	79.2° 22:45	10.74	39%	90.7°
2043-11-09 Mon	100	—	unknown	18:45–04:15 (good, 9.5 h)	79.2° 22:40	10.77	49%	78.8°
2043-11-10 Tue	100	—	unknown	18:45–04:10 (good, 9.42 h)	79.2° 22:40	10.8	59%	66.7°
2043-11-11 Wed	96	—	unknown	19:15–04:05 (good, 8.83 h)	79.2° 22:35	10.84	69%	54.2°
2043-11-12 Thu	87	—	unknown	00:15–04:00 (good, 3.75 h)	79.2° 22:30	10.87	79%	41.6°
2043-11-13 Fri	64	—	unknown	03:50–04:00 (good, 0.17 h)	79.2° 22:25	10.9	87%	29.3°
2043-11-14 Sat	35	—	unknown	18:40–04:00 (marginal, 9.33 h)	79.2° 22:20	10.93	94%	19.2°
2043-11-15 Sun	27	—	unknown	18:40–20:45 (marginal, 2.08 h)	79.2° 22:20	10.96	98%	17.1°
2043-11-16 Mon	27	—	unknown	18:40–21:05 (marginal, 2.42 h)	79.2° 22:15	10.98	100%	25.7°
2043-11-17 Tue	42	—	unknown	18:40–23:45 (marginal, 5.08 h)	79.2° 22:10	11.01	98%	38.5°
2043-11-18 Wed	62	—	unknown	18:40–20:10 (good, 1.5 h)	79.2° 22:05	11.04	94%	52.4°
2043-11-19 Thu	96	—	unknown	18:35–23:45 (good, 5.17 h)	79.2° 22:00	11.07	87%	66.5°
2043-11-20 Fri	100	—	unknown	18:35–02:00 (good, 7.42 h)	79.2° 22:00	11.09	78%	80.4°
2043-11-21 Sat	100	—	unknown	18:35–03:05 (good, 8.5 h)	79.2° 21:55	11.12	68%	94.0°
2043-11-22 Sun	100	—	unknown	18:35–03:10 (good, 8.58 h)	79.2° 21:50	11.14	57%	107.1°
2043-11-23 Mon	100	—	unknown	18:35–03:15 (good, 8.67 h)	79.2° 21:45	11.16	46%	119.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-10-25&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.