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: 07-19 (62), 07-18 (61), 07-17 (59), 07-16 (58), 07-15 (57) — by astronomy; check the weather when the night is within four days.

2043-06-26astronomy score per night — click a bar for that night2043-07-25

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-06-26 Fri	10	—	unknown	02:45–03:40 (marginal, 0.92 h)	79.2° 08:35	4.45	82%	70.1°
2043-06-27 Sat	10	—	unknown	02:40–03:40 (marginal, 1.0 h)	79.2° 08:30	4.47	73%	57.6°
2043-06-28 Sun	11	—	unknown	02:35–03:40 (marginal, 1.08 h)	79.2° 08:30	4.48	63%	45.2°
2043-06-29 Mon	13	—	unknown	02:30–03:40 (marginal, 1.17 h)	79.2° 08:25	4.5	52%	33.1°
2043-06-30 Tue	17	—	unknown	03:15–03:45 (good, 0.5 h)	79.2° 08:20	4.51	41%	22.4°
2043-07-01 Wed	21	—	unknown	03:05–03:45 (good, 0.67 h)	79.2° 08:15	4.53	30%	16.8°
2043-07-02 Thu	25	—	unknown	02:55–03:45 (good, 0.83 h)	79.2° 08:15	4.56	20%	21.6°
2043-07-03 Fri	29	—	unknown	02:40–03:45 (good, 1.08 h)	79.2° 08:10	4.58	11%	32.7°
2043-07-04 Sat	34	—	unknown	02:35–03:45 (good, 1.17 h)	79.2° 08:05	4.61	5%	45.8°
2043-07-05 Sun	35	—	unknown	02:35–03:45 (good, 1.17 h)	79.2° 08:00	4.63	1%	59.5°
2043-07-06 Mon	38	—	unknown	02:30–03:50 (good, 1.33 h)	79.2° 07:55	4.66	0%	73.4°
2043-07-07 Tue	40	—	unknown	02:25–03:50 (good, 1.42 h)	79.2° 07:55	4.69	2%	87.2°
2043-07-08 Wed	41	—	unknown	02:20–03:50 (good, 1.5 h)	79.2° 07:50	4.73	6%	100.6°
2043-07-09 Thu	43	—	unknown	02:20–03:50 (good, 1.5 h)	79.2° 07:45	4.76	13%	113.6°
2043-07-10 Fri	46	—	unknown	02:15–03:55 (good, 1.67 h)	79.2° 07:40	4.8	21%	126.0°
2043-07-11 Sat	48	—	unknown	02:10–03:55 (good, 1.75 h)	79.2° 07:35	4.83	30%	137.8°
2043-07-12 Sun	50	—	unknown	02:05–03:55 (good, 1.83 h)	79.2° 07:35	4.87	39%	148.7°
2043-07-13 Mon	51	—	unknown	02:00–03:55 (good, 1.92 h)	79.2° 07:30	4.91	49%	157.9°
2043-07-14 Tue	54	—	unknown	02:00–04:00 (good, 2.0 h)	79.2° 07:25	4.95	58%	163.1°
2043-07-15 Wed	57	—	unknown	01:55–04:00 (good, 2.08 h)	79.2° 07:20	4.99	67%	161.0°
2043-07-16 Thu	58	—	unknown	01:50–04:00 (good, 2.17 h)	79.2° 07:20	5.04	76%	153.4°
2043-07-17 Fri	59	—	unknown	01:55–04:00 (good, 2.08 h)	79.2° 07:15	5.08	84%	143.5°
2043-07-18 Sat	61	—	unknown	01:50–04:05 (good, 2.25 h)	79.2° 07:10	5.13	90%	132.7°
2043-07-19 Sun	62	—	unknown	01:45–04:05 (good, 2.33 h)	79.2° 07:05	5.17	95%	121.4°
2043-07-20 Mon	52	—	unknown	01:50–04:05 (good, 2.25 h)	79.2° 07:00	5.22	98%	109.7°
2043-07-21 Tue	46	—	unknown	01:55–04:10 (good, 2.25 h)	79.2° 07:00	5.27	100%	97.7°
2043-07-22 Wed	38	—	unknown	02:30–04:10 (good, 1.67 h)	79.2° 06:55	5.32	99%	85.5°
2043-07-23 Thu	31	—	unknown	03:40–04:10 (good, 0.5 h)	79.2° 06:50	5.37	96%	73.0°
2043-07-24 Fri	27	—	unknown	01:00–04:15 (marginal, 3.25 h)	79.2° 06:45	5.42	92%	60.5°
2043-07-25 Sat	23	—	unknown	01:00–04:15 (marginal, 3.25 h)	79.2° 06:40	5.47	85%	47.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-06-26&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.