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 (80), 11-04 (79), 11-05 (79), 11-08 (79) — by astronomy; check the weather when the night is within four days.

2039-10-27astronomy score per night — click a bar for that night2039-11-25

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2039-10-27 Thu	49	—	unknown	20:00–22:25 (good, 2.42 h)	87.1° 17:35	10.31	84%	81.8°
2039-10-28 Fri	50	—	unknown	19:55–22:15 (good, 2.33 h)	87.1° 17:30	10.35	91%	87.3°
2039-10-29 Sat	52	—	unknown	19:55–22:20 (good, 2.42 h)	87.1° 17:30	10.38	96%	92.9°
2039-10-30 Sun	55	—	unknown	18:55–21:35 (good, 2.67 h)	87.1° 16:25	10.42	99%	98.3°
2039-10-31 Mon	58	—	unknown	18:55–21:50 (good, 2.92 h)	87.1° 16:20	10.46	100%	103.3°
2039-11-01 Tue	63	—	unknown	18:50–21:50 (good, 3.0 h)	87.1° 16:15	10.5	99%	107.6°
2039-11-02 Wed	67	—	unknown	18:50–21:50 (good, 3.0 h)	87.1° 16:10	10.53	96%	111.2°
2039-11-03 Thu	77	—	unknown	18:50–21:50 (good, 3.0 h)	87.1° 16:10	10.57	92%	113.8°
2039-11-04 Fri	79	—	unknown	18:50–21:50 (good, 3.0 h)	87.1° 16:05	10.6	86%	115.4°
2039-11-05 Sat	79	—	unknown	18:50–21:50 (good, 3.0 h)	87.1° 16:00	10.64	79%	115.8°
2039-11-06 Sun	81	—	unknown	18:45–21:50 (good, 3.08 h)	87.1° 15:55	10.67	71%	115.1°
2039-11-07 Mon	80	—	unknown	18:45–21:50 (good, 3.08 h)	87.1° 15:55	10.71	62%	113.2°
2039-11-08 Tue	79	—	unknown	18:45–21:50 (good, 3.08 h)	87.1° 15:50	10.74	52%	110.2°
2039-11-09 Wed	77	—	unknown	18:45–21:45 (good, 3.0 h)	87.1° 15:45	10.77	42%	106.3°
2039-11-10 Thu	75	—	unknown	18:45–21:40 (good, 2.92 h)	87.1° 15:40	10.8	33%	101.5°
2039-11-11 Fri	74	—	unknown	18:45–21:35 (good, 2.83 h)	87.1° 15:35	10.83	23%	96.1°
2039-11-12 Sat	73	—	unknown	18:40–21:30 (good, 2.83 h)	87.1° 15:35	10.87	15%	90.3°
2039-11-13 Sun	71	—	unknown	18:40–21:30 (good, 2.83 h)	87.1° 15:30	10.9	8%	84.2°
2039-11-14 Mon	69	—	unknown	18:40–21:25 (good, 2.75 h)	87.1° 15:25	10.93	3%	78.3°
2039-11-15 Tue	68	—	unknown	18:40–21:20 (good, 2.67 h)	87.1° 15:20	10.95	0%	72.8°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2039-10-27&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.