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 Seven Sisters: 10-20 (100), 10-21 (100), 10-22 (100), 10-23 (100), 10-24 (100) — by astronomy; check the weather when the night is within four days.

2047-10-20astronomy score per night — click a bar for that night2047-11-18

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-10-20 Sun	100	—	unknown	22:05–06:10 (good, 8.08 h)	72.6° 03:15	10.03	5%	172.9°
2047-10-21 Mon	100	—	unknown	22:05–06:10 (good, 8.08 h)	72.6° 03:10	10.07	11%	172.0°
2047-10-22 Tue	100	—	unknown	22:00–06:10 (good, 8.17 h)	72.6° 03:05	10.11	20%	157.3°
2047-10-23 Wed	100	—	unknown	21:55–06:15 (good, 8.33 h)	72.6° 03:00	10.15	30%	143.0°
2047-10-24 Thu	100	—	unknown	21:55–06:15 (good, 8.33 h)	72.6° 02:55	10.19	40%	129.1°
2047-10-25 Fri	100	—	unknown	21:55–06:15 (good, 8.33 h)	72.6° 02:55	10.23	51%	115.6°
2047-10-26 Sat	100	—	unknown	21:55–05:15 (good, 8.33 h)	72.6° 02:50	10.27	62%	102.5°
2047-10-27 Sun	100	—	unknown	21:00–05:15 (good, 8.25 h)	72.6° 01:45	10.31	71%	89.7°
2047-10-28 Mon	100	—	unknown	21:55–05:20 (good, 7.42 h)	72.6° 01:40	10.35	80%	77.2°
2047-10-29 Tue	100	—	unknown	23:35–05:20 (good, 5.75 h)	72.6° 01:35	10.39	87%	64.9°
2047-10-30 Wed	92	—	unknown	02:40–05:20 (good, 2.67 h)	72.6° 01:35	10.42	93%	52.8°
2047-10-31 Thu	54	—	unknown	20:50–05:20 (marginal, 8.5 h)	72.6° 01:30	10.46	97%	40.8°
2047-11-01 Fri	32	—	unknown	01:55–05:20 (marginal, 3.42 h)	72.6° 01:25	10.5	99%	28.9°
2047-11-02 Sat	26	—	unknown	03:00–05:25 (marginal, 2.42 h)	72.6° 01:20	10.53	100%	17.0°
2047-11-03 Sun	22	—	unknown	04:10–05:25 (marginal, 1.25 h)	72.6° 01:20	10.57	99%	5.2°
2047-11-04 Mon	27	—	unknown	20:10–23:25 (marginal, 3.25 h)	72.6° 01:15	10.61	96%	6.8°
2047-11-05 Tue	36	—	unknown	19:55–01:25 (marginal, 5.5 h)	72.6° 01:10	10.64	91%	18.6°
2047-11-06 Wed	50	—	unknown	19:35–05:30 (marginal, 9.92 h)	72.6° 01:05	10.67	85%	30.5°
2047-11-07 Thu	82	—	unknown	21:00–23:20 (good, 2.33 h)	72.6° 01:00	10.71	77%	42.6°
2047-11-08 Fri	90	—	unknown	19:50–03:05 (good, 7.25 h)	72.6° 01:00	10.74	69%	54.8°
2047-11-09 Sat	98	—	unknown	19:50–04:55 (good, 9.08 h)	72.6° 00:55	10.77	59%	67.3°
2047-11-10 Sun	100	—	unknown	19:45–05:30 (good, 9.75 h)	72.6° 00:50	10.81	49%	80.2°
2047-11-11 Mon	100	—	unknown	19:40–05:35 (good, 9.92 h)	72.6° 00:45	10.84	38%	93.4°
2047-11-12 Tue	100	—	unknown	19:35–05:35 (good, 10.0 h)	72.6° 00:40	10.87	28%	107.0°
2047-11-13 Wed	100	—	unknown	19:30–05:35 (good, 10.08 h)	72.6° 00:40	10.9	18%	121.2°
2047-11-14 Thu	100	—	unknown	19:30–05:35 (good, 10.08 h)	72.6° 00:35	10.93	10%	135.7°
2047-11-15 Fri	100	—	unknown	19:25–05:35 (good, 10.17 h)	72.6° 00:30	10.96	4%	150.7°
2047-11-16 Sat	100	—	unknown	19:20–05:40 (good, 10.33 h)	72.6° 00:25	10.98	1%	165.8°
2047-11-17 Sun	100	—	unknown	19:15–05:35 (good, 10.33 h)	72.6° 00:25	11.01	0%	178.5°
2047-11-18 Mon	100	—	unknown	19:15–05:30 (good, 10.25 h)	72.6° 00:20	11.04	3%	163.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-10-20&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.