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: 01-06 (100), 01-07 (100), 01-08 (100), 01-09 (100), 01-10 (100) — by astronomy; check the weather when the night is within four days.

2033-12-29astronomy score per night — click a bar for that night2034-01-27

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-12-29 Thu	86	—	unknown	19:35–02:45 (good, 7.17 h)	72.5° 21:35	11.48	60%	39.6°
2033-12-30 Fri	60	—	unknown	18:40–03:10 (marginal, 8.5 h)	72.5° 21:30	11.47	71%	25.8°
2033-12-31 Sat	42	—	unknown	18:45–02:55 (marginal, 8.17 h)	72.5° 21:25	11.46	81%	13.1°
2034-01-01 Sun	28	—	unknown	18:45–02:35 (marginal, 7.83 h)	72.5° 21:25	11.45	89%	9.1°
2034-01-02 Mon	24	—	unknown	18:45–20:50 (marginal, 2.08 h)	72.5° 21:20	11.44	95%	20.0°
2034-01-03 Tue	27	—	unknown	18:45–21:35 (marginal, 2.83 h)	72.5° 21:15	11.43	99%	33.5°
2034-01-04 Wed	45	—	unknown	18:45–01:30 (marginal, 6.75 h)	72.5° 21:10	11.41	100%	47.1°
2034-01-05 Thu	67	—	unknown	18:45–20:30 (good, 1.75 h)	72.5° 21:10	11.4	98%	60.6°
2034-01-06 Fri	100	—	unknown	18:50–23:20 (good, 4.5 h)	72.5° 21:05	11.39	95%	73.8°
2034-01-07 Sat	100	—	unknown	18:50–00:55 (good, 6.08 h)	72.5° 21:00	11.37	89%	86.7°
2034-01-08 Sun	100	—	unknown	18:50–01:45 (good, 6.92 h)	72.5° 20:55	11.36	82%	99.2°
2034-01-09 Mon	100	—	unknown	18:50–01:50 (good, 7.0 h)	72.5° 20:50	11.34	74%	111.4°
2034-01-10 Tue	100	—	unknown	18:50–01:50 (good, 7.0 h)	72.5° 20:50	11.32	65%	123.4°
2034-01-11 Wed	100	—	unknown	18:50–01:50 (good, 7.0 h)	72.5° 20:45	11.3	56%	135.1°
2034-01-12 Thu	100	—	unknown	18:55–01:50 (good, 6.92 h)	72.5° 20:40	11.29	46%	146.7°
2034-01-13 Fri	100	—	unknown	18:55–01:45 (good, 6.83 h)	72.5° 20:35	11.27	37%	157.9°
2034-01-14 Sat	100	—	unknown	18:55–01:45 (good, 6.83 h)	72.5° 20:30	11.24	28%	168.1°
2034-01-15 Sun	100	—	unknown	18:55–01:40 (good, 6.75 h)	72.5° 20:30	11.22	20%	171.1°
2034-01-16 Mon	100	—	unknown	18:55–01:35 (good, 6.67 h)	72.5° 20:25	11.2	13%	162.3°
2034-01-17 Tue	100	—	unknown	19:00–01:30 (good, 6.5 h)	72.5° 20:20	11.18	7%	150.6°
2034-01-18 Wed	100	—	unknown	19:00–01:25 (good, 6.42 h)	72.5° 20:15	11.16	3%	138.1°
2034-01-19 Thu	100	—	unknown	19:00–01:25 (good, 6.42 h)	72.5° 20:15	11.13	0%	125.1°
2034-01-20 Fri	100	—	unknown	19:00–01:20 (good, 6.33 h)	72.5° 20:10	11.11	0%	111.8°
2034-01-21 Sat	100	—	unknown	19:00–01:15 (good, 6.25 h)	72.5° 20:05	11.08	3%	98.2°
2034-01-22 Sun	100	—	unknown	19:05–01:10 (good, 6.08 h)	72.5° 20:00	11.05	8%	84.4°
2034-01-23 Mon	100	—	unknown	19:05–01:10 (good, 6.08 h)	72.5° 19:55	11.03	15%	70.5°
2034-01-24 Tue	98	—	unknown	19:05–01:05 (good, 6.0 h)	72.5° 19:55	11.0	24%	56.5°
2034-01-25 Wed	89	—	unknown	19:05–01:00 (good, 5.92 h)	72.5° 19:50	10.97	34%	42.6°
2034-01-26 Thu	77	—	unknown	19:10–00:55 (good, 5.75 h)	72.5° 19:45	10.94	45%	28.9°
2034-01-27 Fri	59	—	unknown	20:45–23:20 (good, 2.58 h)	72.5° 19:40	10.91	57%	15.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-12-29&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.