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: 11-16 (67), 11-17 (65), 11-18 (62), 11-19 (57), 11-20 (50) — by astronomy; check the weather when the night is within four days.

2039-11-16astronomy score per night — click a bar for that night2039-12-15

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2039-11-16 Wed	67	—	unknown	18:40–21:15 (good, 2.58 h)	87.1° 15:15	10.98	1%	68.4°
2039-11-17 Thu	65	—	unknown	18:40–21:15 (good, 2.58 h)	87.1° 15:15	11.01	4%	65.4°
2039-11-18 Fri	62	—	unknown	18:40–21:10 (good, 2.5 h)	87.1° 15:10	11.04	10%	64.2°
2039-11-19 Sat	57	—	unknown	18:35–21:05 (good, 2.5 h)	87.1° 15:05	11.06	19%	64.8°
2039-11-20 Sun	50	—	unknown	18:35–20:55 (good, 2.33 h)	87.1° 15:00	11.09	29%	67.2°
2039-11-21 Mon	44	—	unknown	18:35–20:45 (good, 2.17 h)	87.1° 15:00	11.12	39%	70.9°
2039-11-22 Tue	39	—	unknown	18:35–20:35 (good, 2.0 h)	87.1° 14:55	11.14	50%	75.5°
2039-11-23 Wed	35	—	unknown	18:35–20:25 (good, 1.83 h)	87.1° 14:50	11.16	61%	80.7°
2039-11-24 Thu	32	—	unknown	18:35–20:15 (good, 1.67 h)	87.1° 14:45	11.19	71%	86.2°
2039-11-25 Fri	31	—	unknown	18:35–20:10 (good, 1.58 h)	87.1° 14:40	11.21	80%	91.7°
2039-11-26 Sat	31	—	unknown	18:35–20:10 (good, 1.58 h)	87.1° 14:40	11.23	87%	97.0°
2039-11-27 Sun	31	—	unknown	18:35–20:05 (good, 1.5 h)	87.1° 14:35	11.25	93%	102.1°
2039-11-28 Mon	31	—	unknown	18:35–20:05 (good, 1.5 h)	87.1° 14:30	11.27	97%	106.5°
2039-11-29 Tue	32	—	unknown	18:35–20:05 (good, 1.5 h)	87.1° 14:25	11.29	99%	110.3°
2039-11-30 Wed	33	—	unknown	18:35–20:05 (good, 1.5 h)	87.1° 14:20	11.31	100%	113.2°
2039-12-01 Thu	34	—	unknown	18:35–20:05 (good, 1.5 h)	87.1° 14:20	11.33	99%	115.1°
2039-12-02 Fri	34	—	unknown	18:35–20:00 (good, 1.42 h)	87.1° 14:15	11.35	96%	115.8°
2039-12-03 Sat	38	—	unknown	18:35–20:00 (good, 1.42 h)	87.1° 14:10	11.36	91%	115.3°
2039-12-04 Sun	39	—	unknown	18:35–19:55 (good, 1.33 h)	87.1° 14:05	11.38	85%	113.7°
2039-12-05 Mon	38	—	unknown	18:35–20:00 (good, 1.42 h)	87.1° 14:05	11.39	77%	111.1°
2039-12-06 Tue	36	—	unknown	18:35–20:00 (good, 1.42 h)	87.1° 14:00	11.41	69%	107.5°
2039-12-07 Wed	35	—	unknown	18:35–19:55 (good, 1.33 h)	87.1° 13:55	11.42	59%	103.1°
2039-12-08 Thu	33	—	unknown	18:35–19:50 (good, 1.25 h)	87.1° 13:50	11.43	49%	98.0°
2039-12-09 Fri	32	—	unknown	18:35–19:45 (good, 1.17 h)	87.1° 13:45	11.44	39%	92.5°
2039-12-10 Sat	31	—	unknown	18:35–19:40 (good, 1.08 h)	87.1° 13:45	11.45	29%	86.7°
2039-12-11 Sun	29	—	unknown	18:35–19:40 (good, 1.08 h)	87.1° 13:40	11.46	19%	80.8°
2039-12-12 Mon	28	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 13:35	11.47	11%	75.2°
2039-12-13 Tue	26	—	unknown	18:35–19:30 (good, 0.92 h)	87.1° 13:30	11.48	5%	70.3°
2039-12-14 Wed	26	—	unknown	18:35–19:25 (good, 0.83 h)	87.1° 13:25	11.48	1%	66.6°
2039-12-15 Thu	24	—	unknown	18:35–19:25 (good, 0.83 h)	87.1° 13:25	11.49	0%	64.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2039-11-16&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.