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 Vega: 08-06 (100), 08-07 (100), 08-08 (100), 08-09 (100), 08-10 (100) — by astronomy; check the weather when the night is within four days.

2043-08-06astronomy score per night — click a bar for that night2043-09-04

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-08-06 Thu	100	—	unknown	22:25–04:35 (good, 6.17 h)	87.1° 23:00	6.12	4%	105.0°
2043-08-07 Fri	100	—	unknown	22:25–04:35 (good, 6.17 h)	87.1° 22:55	6.18	9%	100.6°
2043-08-08 Sat	100	—	unknown	22:20–04:35 (good, 6.25 h)	87.1° 22:50	6.23	16%	95.9°
2043-08-09 Sun	100	—	unknown	22:20–04:40 (good, 6.33 h)	87.1° 22:45	6.29	24%	91.0°
2043-08-10 Mon	100	—	unknown	22:20–04:40 (good, 6.33 h)	87.1° 22:45	6.35	33%	86.2°
2043-08-11 Tue	100	—	unknown	22:15–04:40 (good, 6.42 h)	87.1° 22:40	6.41	42%	81.6°
2043-08-12 Wed	100	—	unknown	22:15–04:35 (good, 6.33 h)	87.1° 22:35	6.46	51%	77.4°
2043-08-13 Thu	100	—	unknown	22:15–04:30 (good, 6.25 h)	87.1° 22:30	6.52	61%	73.7°
2043-08-14 Fri	100	—	unknown	22:10–04:25 (good, 6.25 h)	87.1° 22:25	6.58	70%	70.6°
2043-08-15 Sat	96	—	unknown	22:10–04:20 (good, 6.17 h)	87.1° 22:25	6.64	78%	68.3°
2043-08-16 Sun	89	—	unknown	22:05–04:20 (good, 6.25 h)	87.1° 22:20	6.69	86%	67.0°
2043-08-17 Mon	81	—	unknown	22:05–04:15 (good, 6.17 h)	87.1° 22:15	6.75	92%	66.8°
2043-08-18 Tue	66	—	unknown	22:05–02:05 (good, 4.0 h)	87.1° 22:10	6.81	97%	67.7°
2043-08-19 Wed	67	—	unknown	22:00–01:15 (good, 3.25 h)	87.1° 22:05	6.87	99%	69.9°
2043-08-20 Thu	69	—	unknown	22:00–01:05 (good, 3.08 h)	87.1° 22:05	6.92	100%	73.2°
2043-08-21 Fri	73	—	unknown	21:55–01:25 (good, 3.5 h)	87.1° 22:00	6.98	98%	77.4°
2043-08-22 Sat	78	—	unknown	21:55–01:55 (good, 4.0 h)	87.1° 21:55	7.04	94%	82.4°
2043-08-23 Sun	82	—	unknown	21:55–02:35 (good, 4.67 h)	87.1° 21:50	7.1	87%	87.8°
2043-08-24 Mon	100	—	unknown	21:50–03:15 (good, 5.42 h)	87.1° 21:50	7.15	78%	93.4°
2043-08-25 Tue	100	—	unknown	21:50–03:20 (good, 5.5 h)	87.1° 21:45	7.21	68%	98.8°
2043-08-26 Wed	100	—	unknown	21:50–03:25 (good, 5.58 h)	87.1° 21:40	7.27	57%	103.8°
2043-08-27 Thu	100	—	unknown	21:45–03:25 (good, 5.67 h)	87.1° 21:35	7.32	46%	107.9°
2043-08-28 Fri	100	—	unknown	21:45–03:25 (good, 5.67 h)	87.1° 21:30	7.38	34%	111.0°
2043-08-29 Sat	100	—	unknown	21:40–03:25 (good, 5.75 h)	87.1° 21:30	7.44	24%	112.8°
2043-08-30 Sun	100	—	unknown	21:40–03:20 (good, 5.67 h)	87.1° 21:25	7.49	15%	113.2°
2043-08-31 Mon	100	—	unknown	21:40–03:20 (good, 5.67 h)	87.1° 21:20	7.55	8%	112.2°
2043-09-01 Tue	100	—	unknown	21:35–03:15 (good, 5.67 h)	87.1° 21:15	7.6	3%	109.8°
2043-09-02 Wed	100	—	unknown	21:35–03:10 (good, 5.58 h)	87.1° 21:10	7.66	0%	106.5°
2043-09-03 Thu	100	—	unknown	21:30–03:10 (good, 5.67 h)	87.1° 21:10	7.72	0%	102.3°
2043-09-04 Fri	100	—	unknown	21:30–03:05 (good, 5.58 h)	87.1° 21:05	7.77	2%	97.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-08-06&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.