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: 12-07 (100), 12-08 (100), 12-09 (100), 12-10 (100), 12-11 (100) — by astronomy; check the weather when the night is within four days.

2047-11-29astronomy score per night — click a bar for that night2047-12-28

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-11-29 Fri	39	—	unknown	23:45–05:00 (marginal, 5.25 h)	72.6° 23:35	11.29	94%	20.0°
2047-11-30 Sat	28	—	unknown	01:30–04:40 (marginal, 3.17 h)	72.6° 23:30	11.31	98%	8.2°
2047-12-01 Sun	24	—	unknown	18:35–20:05 (marginal, 1.5 h)	72.6° 23:30	11.33	100%	3.8°
2047-12-02 Mon	27	—	unknown	18:35–21:30 (marginal, 2.92 h)	72.6° 23:25	11.35	100%	15.7°
2047-12-03 Tue	34	—	unknown	18:35–22:35 (marginal, 4.0 h)	72.6° 23:20	11.36	98%	27.6°
2047-12-04 Wed	52	—	unknown	18:10–02:25 (marginal, 8.25 h)	72.6° 23:15	11.38	95%	39.7°
2047-12-05 Thu	87	—	unknown	18:35–21:50 (good, 3.25 h)	72.6° 23:10	11.39	90%	52.0°
2047-12-06 Fri	95	—	unknown	18:35–01:10 (good, 6.58 h)	72.6° 23:10	11.41	83%	64.3°
2047-12-07 Sat	100	—	unknown	18:35–02:50 (good, 8.25 h)	72.6° 23:05	11.42	74%	76.9°
2047-12-08 Sun	100	—	unknown	18:35–03:50 (good, 9.25 h)	72.6° 23:00	11.43	65%	89.8°
2047-12-09 Mon	100	—	unknown	18:35–03:55 (good, 9.33 h)	72.6° 22:55	11.44	55%	102.9°
2047-12-10 Tue	100	—	unknown	18:35–04:00 (good, 9.42 h)	72.6° 22:50	11.45	44%	116.5°
2047-12-11 Wed	100	—	unknown	18:35–03:55 (good, 9.33 h)	72.6° 22:50	11.46	33%	130.3°
2047-12-12 Thu	100	—	unknown	18:35–03:55 (good, 9.33 h)	72.6° 22:45	11.47	22%	144.6°
2047-12-13 Fri	100	—	unknown	18:35–03:50 (good, 9.25 h)	72.6° 22:40	11.48	14%	159.3°
2047-12-14 Sat	100	—	unknown	18:35–03:50 (good, 9.25 h)	72.6° 22:35	11.48	6%	174.2°
2047-12-15 Sun	100	—	unknown	18:35–03:45 (good, 9.17 h)	72.6° 22:35	11.49	2%	170.6°
2047-12-16 Mon	100	—	unknown	18:35–03:40 (good, 9.08 h)	72.6° 22:30	11.5	0%	155.6°
2047-12-17 Tue	100	—	unknown	18:35–03:35 (good, 9.0 h)	72.6° 22:25	11.5	1%	140.6°
2047-12-18 Wed	100	—	unknown	18:35–03:30 (good, 8.92 h)	72.6° 22:20	11.5	5%	125.9°
2047-12-19 Thu	100	—	unknown	18:35–03:30 (good, 8.92 h)	72.6° 22:15	11.51	12%	111.7°
2047-12-20 Fri	100	—	unknown	18:35–03:25 (good, 8.83 h)	72.6° 22:15	11.51	20%	97.9°
2047-12-21 Sat	100	—	unknown	18:35–03:20 (good, 8.75 h)	72.6° 22:10	11.51	29%	84.6°
2047-12-22 Sun	100	—	unknown	18:35–03:15 (good, 8.67 h)	72.6° 22:05	11.51	39%	71.7°
2047-12-23 Mon	98	—	unknown	18:40–03:10 (good, 8.5 h)	72.6° 22:00	11.51	48%	59.2°
2047-12-24 Tue	90	—	unknown	19:10–03:10 (good, 8.0 h)	72.6° 21:55	11.5	58%	47.0°
2047-12-25 Wed	82	—	unknown	23:15–03:05 (good, 3.83 h)	72.6° 21:55	11.5	68%	35.0°
2047-12-26 Thu	52	—	unknown	18:40–03:30 (marginal, 8.83 h)	72.6° 21:50	11.5	76%	23.2°
2047-12-27 Fri	39	—	unknown	18:40–03:10 (marginal, 8.5 h)	72.6° 21:45	11.49	84%	11.4°
2047-12-28 Sat	27	—	unknown	18:40–02:50 (marginal, 8.17 h)	72.6° 21:40	11.49	90%	1.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-11-29&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.