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: 11-06 (81), 11-07 (77), 11-08 (70), 11-09 (63), 11-10 (55) — by astronomy; check the weather when the night is within four days.

2040-11-06astronomy score per night — click a bar for that night2040-12-05

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2040-11-06 Tue	81	—	unknown	18:45–21:55 (good, 3.17 h)	87.1° 15:55	10.7	6%	68.1°
2040-11-07 Wed	77	—	unknown	18:45–21:50 (good, 3.08 h)	87.1° 15:50	10.73	12%	66.1°
2040-11-08 Thu	70	—	unknown	18:45–21:45 (good, 3.0 h)	87.1° 15:45	10.76	21%	65.6°
2040-11-09 Fri	63	—	unknown	18:45–21:40 (good, 2.92 h)	87.1° 15:40	10.8	31%	66.8°
2040-11-10 Sat	55	—	unknown	18:45–21:25 (good, 2.67 h)	87.1° 15:40	10.83	42%	69.4°
2040-11-11 Sun	49	—	unknown	18:40–21:15 (good, 2.58 h)	87.1° 15:35	10.86	53%	73.3°
2040-11-12 Mon	43	—	unknown	18:40–21:05 (good, 2.42 h)	87.1° 15:30	10.89	64%	78.0°
2040-11-13 Tue	39	—	unknown	18:40–20:50 (good, 2.17 h)	87.1° 15:25	10.92	75%	83.3°
2040-11-14 Wed	38	—	unknown	18:40–20:30 (good, 1.83 h)	87.1° 15:20	10.95	84%	88.9°
2040-11-15 Thu	38	—	unknown	18:40–20:30 (good, 1.83 h)	87.1° 15:20	10.98	91%	94.5°
2040-11-16 Fri	39	—	unknown	18:40–20:40 (good, 2.0 h)	87.1° 15:15	11.0	96%	99.8°
2040-11-17 Sat	40	—	unknown	18:40–20:40 (good, 2.0 h)	87.1° 15:10	11.03	99%	104.6°
2040-11-18 Sun	44	—	unknown	18:35–20:45 (good, 2.17 h)	87.1° 15:05	11.06	100%	108.6°
2040-11-19 Mon	45	—	unknown	18:35–20:45 (good, 2.17 h)	87.1° 15:05	11.08	99%	111.7°
2040-11-20 Tue	47	—	unknown	18:35–20:45 (good, 2.17 h)	87.1° 15:00	11.11	95%	113.6°
2040-11-21 Wed	53	—	unknown	18:35–20:40 (good, 2.08 h)	87.1° 14:55	11.13	90%	114.4°
2040-11-22 Thu	54	—	unknown	18:35–20:40 (good, 2.08 h)	87.1° 14:50	11.16	84%	114.0°
2040-11-23 Fri	55	—	unknown	18:35–20:45 (good, 2.17 h)	87.1° 14:45	11.18	76%	112.5°
2040-11-24 Sat	54	—	unknown	18:35–20:40 (good, 2.08 h)	87.1° 14:45	11.2	68%	110.1°
2040-11-25 Sun	52	—	unknown	18:35–20:40 (good, 2.08 h)	87.1° 14:40	11.23	59%	106.8°
2040-11-26 Mon	50	—	unknown	18:35–20:35 (good, 2.0 h)	87.1° 14:35	11.25	50%	102.8°
2040-11-27 Tue	48	—	unknown	18:35–20:30 (good, 1.92 h)	87.1° 14:30	11.27	40%	98.2°
2040-11-28 Wed	47	—	unknown	18:35–20:25 (good, 1.83 h)	87.1° 14:25	11.29	31%	93.3°
2040-11-29 Thu	46	—	unknown	18:35–20:25 (good, 1.83 h)	87.1° 14:25	11.31	22%	88.1°
2040-11-30 Fri	44	—	unknown	18:35–20:20 (good, 1.75 h)	87.1° 14:20	11.32	14%	82.8°
2040-12-01 Sat	42	—	unknown	18:35–20:15 (good, 1.67 h)	87.1° 14:15	11.34	7%	77.7°
2040-12-02 Sun	41	—	unknown	18:35–20:10 (good, 1.58 h)	87.1° 14:10	11.36	2%	73.0°
2040-12-03 Mon	40	—	unknown	18:35–20:05 (good, 1.5 h)	87.1° 14:10	11.37	0%	69.2°
2040-12-04 Tue	38	—	unknown	18:35–20:05 (good, 1.5 h)	87.1° 14:05	11.39	1%	66.6°
2040-12-05 Wed	36	—	unknown	18:35–20:00 (good, 1.42 h)	87.1° 14:00	11.4	4%	65.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2040-11-06&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.