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: 06-13 (100), 06-14 (100), 06-15 (100), 06-16 (100), 06-17 (100) — by astronomy; check the weather when the night is within four days.

2043-06-13astronomy score per night — click a bar for that night2043-07-12

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-06-13 Sat	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:30	4.48	45%	101.5°
2043-06-14 Sun	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:25	4.47	55%	97.0°
2043-06-15 Mon	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:25	4.45	64%	92.3°
2043-06-16 Tue	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:20	4.44	73%	87.5°
2043-06-17 Wed	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:15	4.43	81%	82.9°
2043-06-18 Thu	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:10	4.43	88%	78.6°
2043-06-19 Fri	77	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:05	4.42	93%	74.7°
2043-06-20 Sat	70	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 02:05	4.42	97%	71.4°
2043-06-21 Sun	64	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 02:00	4.42	99%	68.8°
2043-06-22 Mon	61	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:55	4.42	100%	67.2°
2043-06-23 Tue	65	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:50	4.43	98%	66.6°
2043-06-24 Wed	71	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:50	4.43	94%	67.2°
2043-06-25 Thu	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:45	4.44	89%	68.9°
2043-06-26 Fri	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:40	4.45	82%	71.8°
2043-06-27 Sat	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:35	4.47	73%	75.6°
2043-06-28 Sun	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:30	4.48	63%	80.1°
2043-06-29 Mon	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 01:30	4.5	52%	85.3°
2043-06-30 Tue	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:25	4.51	41%	90.8°
2043-07-01 Wed	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:20	4.53	30%	96.4°
2043-07-02 Thu	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:15	4.56	20%	101.7°
2043-07-03 Fri	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:10	4.58	11%	106.4°
2043-07-04 Sat	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:10	4.61	5%	110.2°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-06-13&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.