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: 12-07 (27), 12-08 (23), 12-09 (21), 12-18 (21), 12-19 (20) — by astronomy; check the weather when the night is within four days.

2043-12-07astronomy score per night — click a bar for that night2044-01-05

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-12-07 Mon	27	—	unknown	18:35–19:40 (good, 1.08 h)	87.1° 13:55	11.42	33%	71.2°
2043-12-08 Tue	23	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 13:50	11.43	42%	74.8°
2043-12-09 Wed	21	—	unknown	18:35–19:25 (good, 0.83 h)	87.1° 13:45	11.44	53%	79.2°
2043-12-10 Thu	18	—	unknown	18:35–19:15 (good, 0.67 h)	87.1° 13:45	11.45	64%	84.2°
2043-12-11 Fri	16	—	unknown	18:35–19:05 (good, 0.5 h)	87.1° 13:40	11.46	74%	89.7°
2043-12-12 Sat	16	—	unknown	18:35–19:00 (good, 0.42 h)	87.1° 13:35	11.47	83%	95.4°
2043-12-13 Sun	16	—	unknown	18:35–19:00 (good, 0.42 h)	87.1° 13:30	11.48	91%	101.0°
2043-12-14 Mon	16	—	unknown	18:35–19:00 (good, 0.42 h)	87.1° 13:25	11.49	97%	106.0°
2043-12-15 Tue	17	—	unknown	18:35–19:05 (good, 0.5 h)	87.1° 13:25	11.49	100%	110.1°
2043-12-16 Wed	17	—	unknown	18:35–19:05 (good, 0.5 h)	87.1° 13:20	11.5	99%	112.7°
2043-12-17 Thu	18	—	unknown	18:35–19:05 (good, 0.5 h)	87.1° 13:15	11.5	96%	113.6°
2043-12-18 Fri	21	—	unknown	18:35–19:10 (good, 0.58 h)	87.1° 13:10	11.5	90%	112.9°
2043-12-19 Sat	20	—	unknown	18:35–19:05 (good, 0.5 h)	87.1° 13:10	11.51	82%	110.7°
2043-12-20 Sun	18	—	unknown	18:35–19:05 (good, 0.5 h)	87.1° 13:05	11.51	73%	107.3°
2043-12-21 Mon	16	—	unknown	18:35–19:00 (good, 0.42 h)	87.1° 13:00	11.51	63%	103.1°
2043-12-22 Tue	15	—	unknown	18:35–18:55 (good, 0.33 h)	87.1° 12:55	11.51	53%	98.5°
2043-12-23 Wed	13	—	unknown	18:40–18:50 (good, 0.17 h)	87.1° 12:50	11.51	43%	93.6°
2043-12-24 Thu	12	—	unknown	18:40–18:45 (good, 0.08 h)	87.1° 12:50	11.5	33%	88.7°
2043-12-25 Fri	11	—	unknown	18:40–18:45 (good, 0.08 h)	87.1° 12:45	11.5	25%	84.0°
2043-12-26 Sat	11	—	unknown	18:05–19:10 (marginal, 1.08 h)	87.1° 12:40	11.5	17%	79.5°
2043-12-27 Sun	10	—	unknown	18:40–19:05 (marginal, 0.42 h)	87.1° 12:35	11.49	11%	75.4°
2043-12-28 Mon	10	—	unknown	18:40–19:05 (marginal, 0.42 h)	87.1° 12:30	11.49	6%	71.9°
2043-12-29 Tue	9	—	unknown	18:40–19:00 (marginal, 0.33 h)	87.1° 12:30	11.48	2%	69.1°
2043-12-30 Wed	8	—	unknown	18:40–18:55 (marginal, 0.25 h)	87.1° 12:25	11.47	0%	67.2°
2043-12-31 Thu	8	—	unknown	05:50–06:10 (marginal, 0.33 h)	87.1° 12:20	11.46	0%	66.4°
2044-01-01 Fri	9	—	unknown	05:45–06:10 (marginal, 0.42 h)	87.1° 12:15	11.45	2%	66.6°
2044-01-02 Sat	9	—	unknown	05:45–06:10 (marginal, 0.42 h)	87.1° 12:15	11.44	6%	67.9°
2044-01-03 Sun	10	—	unknown	05:40–06:45 (marginal, 1.08 h)	87.1° 12:10	11.43	11%	70.3°
2044-01-04 Mon	11	—	unknown	06:05–06:10 (good, 0.08 h)	87.1° 12:05	11.42	18%	73.6°
2044-01-05 Tue	12	—	unknown	06:05–06:10 (good, 0.08 h)	87.1° 12:00	11.41	27%	77.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-12-07&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.