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: 08-07 (100), 08-08 (100), 08-09 (100), 08-10 (100), 08-11 (100) — by astronomy; check the weather when the night is within four days.

2029-08-04astronomy score per night — click a bar for that night2029-09-02

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-08-04 Sat	82	—	unknown	00:35–04:30 (good, 3.92 h)	79.1° 06:00	6.03	27%	40.0°
2029-08-05 Sun	93	—	unknown	00:30–04:30 (good, 4.0 h)	79.1° 05:55	6.09	19%	51.6°
2029-08-06 Mon	98	—	unknown	00:25–04:35 (good, 4.17 h)	79.1° 05:55	6.14	11%	63.8°
2029-08-07 Tue	100	—	unknown	00:20–04:35 (good, 4.25 h)	79.1° 05:50	6.2	6%	76.4°
2029-08-08 Wed	100	—	unknown	00:20–04:35 (good, 4.25 h)	79.1° 05:45	6.26	2%	89.5°
2029-08-09 Thu	100	—	unknown	00:15–04:40 (good, 4.42 h)	79.1° 05:40	6.31	0%	102.9°
2029-08-10 Fri	100	—	unknown	00:10–04:40 (good, 4.5 h)	79.1° 05:35	6.37	1%	116.5°
2029-08-11 Sat	100	—	unknown	00:05–04:40 (good, 4.58 h)	79.1° 05:35	6.43	5%	130.1°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-08-04&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.