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: 10-17 (100), 10-18 (100), 10-19 (100), 10-20 (100), 10-21 (100) — by astronomy; check the weather when the night is within four days.

2047-10-17astronomy score per night — click a bar for that night2047-11-15

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-10-17 Thu	100	—	unknown	20:10–00:15 (good, 4.08 h)	87.1° 18:15	9.9	2%	98.3°
2047-10-18 Fri	100	—	unknown	20:10–00:10 (good, 4.0 h)	87.1° 18:10	9.95	0%	91.1°
2047-10-19 Sat	100	—	unknown	20:10–00:05 (good, 3.92 h)	87.1° 18:10	9.99	1%	83.7°
2047-10-20 Sun	100	—	unknown	20:10–00:05 (good, 3.92 h)	87.1° 18:05	10.03	5%	76.7°
2047-10-21 Mon	100	—	unknown	20:05–00:00 (good, 3.92 h)	87.1° 18:00	10.07	11%	70.5°
2047-10-22 Tue	96	—	unknown	20:05–23:55 (good, 3.83 h)	87.1° 17:55	10.11	20%	65.6°
2047-10-23 Wed	84	—	unknown	20:05–23:50 (good, 3.75 h)	87.1° 17:50	10.15	30%	62.3°
2047-10-24 Thu	73	—	unknown	20:00–23:45 (good, 3.75 h)	87.1° 17:50	10.19	40%	60.9°
2047-10-25 Fri	61	—	unknown	20:00–23:25 (good, 3.42 h)	87.1° 17:45	10.23	51%	61.2°
2047-10-26 Sat	52	—	unknown	20:00–23:10 (good, 3.17 h)	87.1° 17:40	10.27	62%	63.2°
2047-10-27 Sun	45	—	unknown	19:00–21:10 (good, 2.17 h)	87.1° 16:35	10.31	71%	66.6°
2047-10-28 Mon	42	—	unknown	18:55–20:20 (good, 1.42 h)	87.1° 16:30	10.35	80%	70.9°
2047-10-29 Tue	40	—	unknown	18:55–20:05 (good, 1.17 h)	87.1° 16:30	10.39	87%	76.0°
2047-10-30 Wed	41	—	unknown	18:55–20:10 (good, 1.25 h)	87.1° 16:25	10.42	93%	81.5°
2047-10-31 Thu	43	—	unknown	18:55–20:25 (good, 1.5 h)	87.1° 16:20	10.46	97%	87.3°
2047-11-01 Fri	47	—	unknown	18:50–20:50 (good, 2.0 h)	87.1° 16:15	10.5	99%	93.1°
2047-11-02 Sat	53	—	unknown	18:50–21:20 (good, 2.5 h)	87.1° 16:10	10.53	100%	98.8°
2047-11-03 Sun	57	—	unknown	18:50–21:40 (good, 2.83 h)	87.1° 16:10	10.57	99%	104.2°
2047-11-04 Mon	62	—	unknown	18:50–21:45 (good, 2.92 h)	87.1° 16:05	10.61	96%	109.1°
2047-11-05 Tue	67	—	unknown	18:50–21:45 (good, 2.92 h)	87.1° 16:00	10.64	91%	113.3°
2047-11-06 Wed	78	—	unknown	18:45–21:45 (good, 3.0 h)	87.1° 15:55	10.67	85%	116.5°
2047-11-07 Thu	79	—	unknown	18:45–21:45 (good, 3.0 h)	87.1° 15:55	10.71	77%	118.6°
2047-11-08 Fri	78	—	unknown	18:45–21:45 (good, 3.0 h)	87.1° 15:50	10.74	69%	119.3°
2047-11-09 Sat	77	—	unknown	18:45–21:45 (good, 3.0 h)	87.1° 15:45	10.77	59%	118.6°
2047-11-10 Sun	75	—	unknown	18:45–21:40 (good, 2.92 h)	87.1° 15:40	10.81	49%	116.3°
2047-11-11 Mon	74	—	unknown	18:45–21:35 (good, 2.83 h)	87.1° 15:35	10.84	38%	112.6°
2047-11-12 Tue	73	—	unknown	18:40–21:30 (good, 2.83 h)	87.1° 15:35	10.87	28%	107.5°
2047-11-13 Wed	71	—	unknown	18:40–21:30 (good, 2.83 h)	87.1° 15:30	10.9	18%	101.4°
2047-11-14 Thu	69	—	unknown	18:40–21:25 (good, 2.75 h)	87.1° 15:25	10.93	10%	94.5°
2047-11-15 Fri	68	—	unknown	18:40–21:20 (good, 2.67 h)	87.1° 15:20	10.96	4%	87.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-10-17&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.