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: 08-10 (100), 08-11 (100), 08-12 (100), 08-13 (100), 08-14 (100) — by astronomy; check the weather when the night is within four days.

2037-08-10astronomy score per night — click a bar for that night2037-09-08

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2037-08-10 Mon	100	—	unknown	00:10–04:40 (good, 4.5 h)	79.1° 05:35	6.37	0%	97.4°
2037-08-11 Tue	100	—	unknown	00:05–04:40 (good, 4.58 h)	79.2° 05:35	6.43	0%	110.9°
2037-08-12 Wed	100	—	unknown	00:00–04:45 (good, 4.75 h)	79.2° 05:30	6.49	3%	124.2°
2037-08-13 Thu	100	—	unknown	00:00–04:45 (good, 4.75 h)	79.2° 05:25	6.55	9%	136.7°
2037-08-14 Fri	100	—	unknown	23:55–04:45 (good, 4.83 h)	79.2° 05:20	6.6	17%	147.4°
2037-08-15 Sat	100	—	unknown	23:50–04:50 (good, 5.0 h)	79.1° 05:20	6.66	27%	154.4°
2037-08-16 Sun	100	—	unknown	23:45–04:50 (good, 5.08 h)	79.2° 05:15	6.72	38%	154.6°
2037-08-17 Mon	100	—	unknown	23:45–04:50 (good, 5.08 h)	79.2° 05:10	6.78	49%	148.4°
2037-08-18 Tue	100	—	unknown	23:45–04:55 (good, 5.17 h)	79.2° 05:05	6.83	60%	139.0°
2037-08-19 Wed	100	—	unknown	23:40–04:55 (good, 5.25 h)	79.2° 05:00	6.89	70%	128.3°
2037-08-20 Thu	100	—	unknown	23:40–04:55 (good, 5.25 h)	79.2° 05:00	6.95	79%	117.1°
2037-08-21 Fri	100	—	unknown	23:45–04:55 (good, 5.17 h)	79.2° 04:55	7.01	86%	105.8°
2037-08-22 Sat	100	—	unknown	23:50–05:00 (good, 5.17 h)	79.2° 04:50	7.06	92%	94.6°
2037-08-23 Sun	80	—	unknown	00:35–05:00 (good, 4.42 h)	79.2° 04:45	7.12	97%	83.5°
2037-08-24 Mon	70	—	unknown	01:50–05:00 (good, 3.17 h)	79.1° 04:40	7.18	99%	72.5°
2037-08-25 Tue	55	—	unknown	04:25–05:05 (good, 0.67 h)	79.2° 04:40	7.24	100%	61.9°
2037-08-26 Wed	42	—	unknown	22:55–05:05 (marginal, 6.17 h)	79.2° 04:35	7.29	99%	51.5°
2037-08-27 Thu	32	—	unknown	22:55–05:05 (marginal, 6.17 h)	79.2° 04:30	7.35	96%	41.9°
2037-08-28 Fri	29	—	unknown	22:50–05:05 (marginal, 6.25 h)	79.2° 04:25	7.41	91%	33.3°
2037-08-29 Sat	34	—	unknown	22:40–05:10 (marginal, 6.5 h)	79.1° 04:25	7.46	85%	26.9°
2037-08-30 Sun	43	—	unknown	22:25–05:10 (marginal, 6.75 h)	79.2° 04:20	7.52	78%	24.5°
2037-08-31 Mon	66	—	unknown	22:45–23:00 (good, 0.25 h)	79.2° 04:15	7.57	69%	27.4°
2037-09-01 Tue	82	—	unknown	22:45–03:55 (good, 5.17 h)	79.2° 04:10	7.63	60%	34.3°
2037-09-02 Wed	87	—	unknown	22:40–05:15 (good, 6.58 h)	79.2° 04:05	7.69	50%	43.7°
2037-09-03 Thu	93	—	unknown	22:35–05:15 (good, 6.67 h)	79.2° 04:05	7.74	40%	54.4°
2037-09-04 Fri	99	—	unknown	22:30–05:15 (good, 6.75 h)	79.2° 04:00	7.8	29%	66.1°
2037-09-05 Sat	100	—	unknown	22:30–05:20 (good, 6.83 h)	79.2° 03:55	7.85	20%	78.5°
2037-09-06 Sun	100	—	unknown	22:25–05:20 (good, 6.92 h)	79.2° 03:50	7.91	12%	91.5°
2037-09-07 Mon	100	—	unknown	22:20–05:20 (good, 7.0 h)	79.1° 03:45	7.96	5%	104.8°
2037-09-08 Tue	100	—	unknown	22:15–05:20 (good, 7.08 h)	79.2° 03:45	8.02	1%	118.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2037-08-10&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.