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: 08-12 (100), 08-13 (100), 08-14 (100), 08-15 (100), 08-16 (100) — by astronomy; check the weather when the night is within four days.

2029-08-12astronomy score per night — click a bar for that night2029-09-10

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-08-12 Sun	100	—	unknown	00:00–04:45 (good, 4.75 h)	79.1° 05:30	6.49	11%	143.5°
2029-08-13 Mon	100	—	unknown	00:00–04:45 (good, 4.75 h)	79.1° 05:25	6.54	19%	155.9°
2029-08-14 Tue	100	—	unknown	23:55–04:45 (good, 4.83 h)	79.1° 05:20	6.6	29%	164.4°
2029-08-15 Wed	100	—	unknown	23:50–04:50 (good, 5.0 h)	79.1° 05:20	6.66	40%	162.4°
2029-08-16 Thu	100	—	unknown	23:45–04:50 (good, 5.08 h)	79.1° 05:15	6.72	52%	152.3°
2029-08-17 Fri	100	—	unknown	23:45–04:50 (good, 5.08 h)	79.1° 05:10	6.77	63%	140.0°
2029-08-18 Sat	100	—	unknown	23:45–04:50 (good, 5.08 h)	79.1° 05:05	6.83	73%	127.1°
2029-08-19 Sun	100	—	unknown	23:45–04:55 (good, 5.17 h)	79.1° 05:00	6.89	82%	114.2°
2029-08-20 Mon	100	—	unknown	23:50–04:55 (good, 5.08 h)	79.1° 05:00	6.95	90%	101.4°
2029-08-21 Tue	100	—	unknown	00:15–04:55 (good, 4.67 h)	79.1° 04:55	7.0	95%	88.7°
2029-08-22 Wed	72	—	unknown	01:40–05:00 (good, 3.33 h)	79.1° 04:50	7.06	98%	76.2°
2029-08-23 Thu	53	—	unknown	04:15–05:00 (good, 0.75 h)	79.1° 04:45	7.12	100%	64.0°
2029-08-24 Fri	38	—	unknown	23:10–05:00 (marginal, 5.83 h)	79.1° 04:40	7.17	99%	52.1°
2029-08-25 Sat	27	—	unknown	23:15–05:05 (marginal, 5.83 h)	79.1° 04:40	7.23	96%	40.6°
2029-08-26 Sun	20	—	unknown	23:10–05:05 (marginal, 5.92 h)	79.1° 04:35	7.29	92%	29.8°
2029-08-27 Mon	26	—	unknown	22:55–05:05 (marginal, 6.17 h)	79.1° 04:30	7.35	86%	20.5°
2029-08-28 Tue	35	—	unknown	22:40–05:05 (marginal, 6.42 h)	79.1° 04:25	7.4	79%	15.2°
2029-08-29 Wed	46	—	unknown	22:30–05:10 (marginal, 6.67 h)	79.1° 04:20	7.46	71%	17.7°
2029-08-30 Thu	61	—	unknown	00:25–02:25 (good, 2.0 h)	79.1° 04:20	7.51	62%	26.0°
2029-08-31 Fri	81	—	unknown	22:45–05:10 (good, 6.42 h)	79.1° 04:15	7.57	52%	36.3°
2029-09-01 Sat	87	—	unknown	22:45–05:10 (good, 6.42 h)	79.1° 04:10	7.63	43%	47.4°
2029-09-02 Sun	95	—	unknown	22:40–05:15 (good, 6.58 h)	79.1° 04:05	7.68	33%	59.2°
2029-09-03 Mon	100	—	unknown	22:35–05:15 (good, 6.67 h)	79.1° 04:05	7.74	24%	71.5°
2029-09-04 Tue	100	—	unknown	22:30–05:15 (good, 6.75 h)	79.1° 04:00	7.79	16%	84.2°
2029-09-05 Wed	100	—	unknown	22:30–05:20 (good, 6.83 h)	79.1° 03:55	7.85	8%	97.3°
2029-09-06 Thu	100	—	unknown	22:25–05:20 (good, 6.92 h)	79.1° 03:50	7.9	3%	110.9°
2029-09-07 Fri	100	—	unknown	22:20–05:20 (good, 7.0 h)	79.1° 03:45	7.96	0%	124.7°
2029-09-08 Sat	100	—	unknown	22:15–05:20 (good, 7.08 h)	79.1° 03:45	8.01	0%	138.4°
2029-09-09 Sun	100	—	unknown	22:10–05:25 (good, 7.25 h)	79.1° 03:40	8.07	3%	151.6°
2029-09-10 Mon	100	—	unknown	22:10–05:25 (good, 7.25 h)	79.1° 03:35	8.12	9%	162.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-08-12&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.