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: 08-02 (100), 08-03 (100), 08-04 (100), 08-05 (100), 08-06 (100) — by astronomy; check the weather when the night is within four days.

2035-07-29astronomy score per night — click a bar for that night2035-08-27

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-07-29 Sun	69	—	unknown	01:00–04:20 (good, 3.33 h)	79.1° 06:25	5.67	30%	36.3°
2035-07-30 Mon	82	—	unknown	00:55–04:20 (good, 3.42 h)	79.1° 06:25	5.73	20%	47.8°
2035-07-31 Tue	93	—	unknown	00:50–04:25 (good, 3.58 h)	79.1° 06:20	5.78	11%	60.6°
2035-08-01 Wed	98	—	unknown	00:45–04:25 (good, 3.67 h)	79.1° 06:15	5.84	5%	74.0°
2035-08-02 Thu	100	—	unknown	00:45–04:25 (good, 3.67 h)	79.1° 06:10	5.89	1%	87.6°
2035-08-03 Fri	100	—	unknown	00:40–04:30 (good, 3.83 h)	79.1° 06:05	5.95	0%	101.2°
2035-08-04 Sat	100	—	unknown	00:35–04:30 (good, 3.92 h)	79.1° 06:05	6.0	2%	114.4°
2035-08-05 Sun	100	—	unknown	00:30–04:30 (good, 4.0 h)	79.1° 06:00	6.06	7%	127.1°
2035-08-06 Mon	100	—	unknown	00:30–04:35 (good, 4.08 h)	79.1° 05:55	6.12	13%	138.6°
2035-08-07 Tue	100	—	unknown	00:25–04:35 (good, 4.17 h)	79.1° 05:50	6.17	22%	148.3°
2035-08-08 Wed	100	—	unknown	00:20–04:35 (good, 4.25 h)	79.1° 05:45	6.23	31%	154.8°
2035-08-09 Thu	100	—	unknown	00:15–04:40 (good, 4.42 h)	79.1° 05:45	6.29	40%	155.9°
2035-08-10 Fri	100	—	unknown	00:15–04:40 (good, 4.42 h)	79.1° 05:40	6.34	50%	151.4°
2035-08-11 Sat	100	—	unknown	00:15–04:40 (good, 4.42 h)	79.1° 05:35	6.4	60%	143.6°
2035-08-12 Sun	100	—	unknown	00:10–04:45 (good, 4.58 h)	79.1° 05:30	6.46	69%	134.3°
2035-08-13 Mon	100	—	unknown	00:10–04:45 (good, 4.58 h)	79.1° 05:25	6.52	77%	124.2°
2035-08-14 Tue	100	—	unknown	00:10–04:45 (good, 4.58 h)	79.1° 05:25	6.57	85%	113.7°
2035-08-15 Wed	100	—	unknown	00:10–04:45 (good, 4.58 h)	79.1° 05:20	6.63	91%	102.9°
2035-08-16 Thu	100	—	unknown	00:25–04:50 (good, 4.42 h)	79.1° 05:15	6.69	96%	91.9°
2035-08-17 Fri	70	—	unknown	01:30–04:50 (good, 3.33 h)	79.1° 05:10	6.75	99%	80.8°
2035-08-18 Sat	55	—	unknown	02:45–04:50 (good, 2.08 h)	79.1° 05:10	6.8	100%	69.6°
2035-08-19 Sun	42	—	unknown	23:25–04:55 (marginal, 5.5 h)	79.1° 05:05	6.86	99%	58.4°
2035-08-20 Mon	32	—	unknown	23:25–04:55 (marginal, 5.5 h)	79.1° 05:00	6.92	96%	47.4°
2035-08-21 Tue	26	—	unknown	23:20–04:55 (marginal, 5.58 h)	79.1° 04:55	6.98	91%	37.1°
2035-08-22 Wed	29	—	unknown	23:10–05:00 (marginal, 5.83 h)	79.1° 04:50	7.03	85%	28.5°
2035-08-23 Thu	39	—	unknown	23:00–05:00 (marginal, 6.0 h)	79.1° 04:50	7.09	76%	24.0°
2035-08-24 Fri	55	—	unknown	23:15–23:20 (good, 0.08 h)	79.1° 04:45	7.15	66%	26.0°
2035-08-25 Sat	82	—	unknown	23:15–05:00 (good, 5.75 h)	79.1° 04:40	7.21	55%	33.7°
2035-08-26 Sun	88	—	unknown	23:10–05:05 (good, 5.92 h)	79.1° 04:35	7.26	44%	44.4°
2035-08-27 Mon	95	—	unknown	23:05–05:05 (good, 6.0 h)	79.1° 04:30	7.32	32%	56.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-07-29&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.