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: 12-02 (100), 12-03 (100), 12-04 (100), 12-05 (100), 12-06 (100) — by astronomy; check the weather when the night is within four days.

2034-12-02astronomy score per night — click a bar for that night2034-12-31

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-12-02 Sat	100	—	unknown	18:35–04:25 (good, 9.83 h)	72.5° 23:20	11.35	48%	103.7°
2034-12-03 Sun	100	—	unknown	18:35–04:25 (good, 9.83 h)	72.5° 23:20	11.36	38%	116.2°
2034-12-04 Mon	100	—	unknown	18:35–04:25 (good, 9.83 h)	72.5° 23:15	11.38	28%	128.3°
2034-12-05 Tue	100	—	unknown	18:35–04:20 (good, 9.75 h)	72.5° 23:10	11.39	20%	140.1°
2034-12-06 Wed	100	—	unknown	18:35–04:15 (good, 9.67 h)	72.5° 23:05	11.41	13%	151.6°
2034-12-07 Thu	100	—	unknown	18:35–04:15 (good, 9.67 h)	72.5° 23:05	11.42	8%	162.5°
2034-12-08 Fri	100	—	unknown	18:35–04:10 (good, 9.58 h)	72.5° 23:00	11.43	3%	170.6°
2034-12-09 Sat	100	—	unknown	18:35–04:05 (good, 9.5 h)	72.5° 22:55	11.44	1%	167.8°
2034-12-10 Sun	100	—	unknown	18:35–04:00 (good, 9.42 h)	72.5° 22:50	11.45	0%	158.0°
2034-12-11 Mon	100	—	unknown	18:35–04:00 (good, 9.42 h)	72.5° 22:45	11.46	1%	146.8°
2034-12-12 Tue	100	—	unknown	18:35–03:55 (good, 9.33 h)	72.5° 22:45	11.47	4%	135.2°
2034-12-13 Wed	100	—	unknown	18:35–03:50 (good, 9.25 h)	72.5° 22:40	11.48	9%	123.3°
2034-12-14 Thu	100	—	unknown	18:35–03:45 (good, 9.17 h)	72.5° 22:35	11.49	15%	111.2°
2034-12-15 Fri	100	—	unknown	18:35–03:40 (good, 9.08 h)	72.5° 22:30	11.49	22%	99.0°
2034-12-16 Sat	100	—	unknown	18:35–03:40 (good, 9.08 h)	72.5° 22:25	11.5	31%	86.4°
2034-12-17 Sun	100	—	unknown	18:35–03:35 (good, 9.0 h)	72.5° 22:25	11.5	41%	73.6°
2034-12-18 Mon	99	—	unknown	18:35–03:30 (good, 8.92 h)	72.5° 22:20	11.5	52%	60.5°
2034-12-19 Tue	91	—	unknown	19:45–03:25 (good, 7.67 h)	72.5° 22:15	11.51	63%	47.1°
2034-12-20 Wed	82	—	unknown	02:40–03:20 (good, 0.67 h)	72.5° 22:10	11.51	74%	33.4°
2034-12-21 Thu	48	—	unknown	18:35–03:40 (marginal, 9.08 h)	72.5° 22:10	11.51	83%	19.9°
2034-12-22 Fri	32	—	unknown	18:35–03:20 (marginal, 8.75 h)	72.5° 22:05	11.51	91%	9.4°
2034-12-23 Sat	25	—	unknown	18:40–20:50 (marginal, 2.17 h)	72.5° 22:00	11.51	97%	15.0°
2034-12-24 Sun	27	—	unknown	18:40–21:15 (marginal, 2.58 h)	72.5° 21:55	11.5	100%	28.6°
2034-12-25 Mon	46	—	unknown	18:40–01:05 (marginal, 6.42 h)	72.5° 21:50	11.5	99%	43.2°
2034-12-26 Tue	65	—	unknown	18:40–20:50 (good, 2.17 h)	72.5° 21:50	11.5	96%	57.7°
2034-12-27 Wed	100	—	unknown	18:40–00:05 (good, 5.42 h)	72.5° 21:45	11.49	91%	72.0°
2034-12-28 Thu	100	—	unknown	18:40–01:45 (good, 7.08 h)	72.5° 21:40	11.48	83%	85.9°
2034-12-29 Fri	100	—	unknown	18:40–02:25 (good, 7.75 h)	72.5° 21:35	11.48	74%	99.4°
2034-12-30 Sat	100	—	unknown	18:40–02:35 (good, 7.92 h)	72.5° 21:30	11.47	65%	112.3°
2034-12-31 Sun	100	—	unknown	18:45–02:35 (good, 7.83 h)	72.5° 21:30	11.46	55%	124.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-12-02&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.