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: 07-05 (100), 07-06 (100), 07-07 (100), 07-08 (100), 07-09 (100) — by astronomy; check the weather when the night is within four days.

2043-07-05astronomy score per night — click a bar for that night2043-08-03

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-07-05 Sun	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:05	4.63	1%	112.6°
2043-07-06 Mon	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.1° 01:00	4.66	0%	113.4°
2043-07-07 Tue	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.1° 00:55	4.69	2%	112.7°
2043-07-08 Wed	100	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:50	4.73	6%	110.5°
2043-07-09 Thu	100	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:50	4.76	13%	107.3°
2043-07-10 Fri	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:45	4.8	21%	103.3°
2043-07-11 Sat	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:40	4.83	30%	98.8°
2043-07-12 Sun	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:35	4.87	39%	94.0°
2043-07-13 Mon	100	—	unknown	23:00–03:55 (good, 4.92 h)	87.1° 00:35	4.91	49%	89.2°
2043-07-14 Tue	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:30	4.95	58%	84.5°
2043-07-15 Wed	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:25	4.99	67%	80.0°
2043-07-16 Thu	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:20	5.04	76%	75.9°
2043-07-17 Fri	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:15	5.08	84%	72.4°
2043-07-18 Sat	99	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:15	5.13	90%	69.6°
2043-07-19 Sun	93	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:10	5.17	95%	67.6°
2043-07-20 Mon	67	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:05	5.22	98%	66.7°
2043-07-21 Tue	67	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 00:00	5.27	100%	66.9°
2043-07-22 Wed	68	—	unknown	22:50–03:15 (good, 4.42 h)	87.1° 23:55	5.32	99%	68.3°
2043-07-23 Thu	72	—	unknown	22:50–03:10 (good, 4.33 h)	87.1° 23:55	5.37	96%	70.8°
2043-07-24 Fri	76	—	unknown	22:50–03:30 (good, 4.67 h)	87.1° 23:50	5.42	92%	74.4°
2043-07-25 Sat	100	—	unknown	22:45–04:00 (good, 5.25 h)	87.1° 23:45	5.47	85%	78.9°
2043-07-26 Sun	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 23:40	5.52	76%	83.9°
2043-07-27 Mon	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 23:40	5.57	66%	89.3°
2043-07-28 Tue	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.1° 23:35	5.62	55%	94.8°
2043-07-29 Wed	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.1° 23:30	5.68	43%	100.1°
2043-07-30 Thu	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.1° 23:25	5.73	32%	105.0°
2043-07-31 Fri	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:20	5.79	22%	108.9°
2043-08-01 Sat	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:20	5.84	13%	111.8°
2043-08-02 Sun	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:15	5.9	6%	113.2°
2043-08-03 Mon	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.1° 23:10	5.95	2%	113.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-07-05&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.