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: 02-16 (62), 02-17 (61), 02-18 (61), 02-15 (60), 02-19 (60) — by astronomy; check the weather when the night is within four days.

2035-01-30astronomy score per night — click a bar for that night2035-02-28

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-01-30 Tue	27	—	unknown	04:45–06:00 (good, 1.25 h)	87.1° 10:20	10.83	53%	76.1°
2035-01-31 Wed	29	—	unknown	04:35–06:00 (good, 1.42 h)	87.1° 10:15	10.8	44%	70.3°
2035-02-01 Thu	33	—	unknown	04:30–06:00 (good, 1.5 h)	87.1° 10:10	10.76	34%	65.4°
2035-02-02 Fri	37	—	unknown	04:20–06:00 (good, 1.67 h)	87.1° 10:05	10.73	26%	61.4°
2035-02-03 Sat	42	—	unknown	04:10–06:00 (good, 1.83 h)	87.1° 10:00	10.7	18%	58.6°
2035-02-04 Sun	45	—	unknown	04:05–05:55 (good, 1.83 h)	87.1° 10:00	10.66	11%	57.2°
2035-02-05 Mon	48	—	unknown	04:00–05:55 (good, 1.92 h)	87.1° 09:55	10.63	6%	57.5°
2035-02-06 Tue	50	—	unknown	03:55–05:55 (good, 2.0 h)	87.1° 09:50	10.59	2%	59.4°
2035-02-07 Wed	51	—	unknown	03:50–05:55 (good, 2.08 h)	87.1° 09:45	10.56	0%	62.9°
2035-02-08 Thu	53	—	unknown	03:50–05:55 (good, 2.08 h)	87.1° 09:40	10.52	0%	67.8°
2035-02-09 Fri	53	—	unknown	03:45–05:50 (good, 2.08 h)	87.1° 09:40	10.48	3%	73.7°
2035-02-10 Sat	54	—	unknown	03:40–05:50 (good, 2.17 h)	87.1° 09:35	10.45	7%	80.4°
2035-02-11 Sun	55	—	unknown	03:35–05:50 (good, 2.25 h)	87.1° 09:30	10.41	14%	87.6°
2035-02-12 Mon	57	—	unknown	03:30–05:50 (good, 2.33 h)	87.1° 09:25	10.37	22%	95.0°
2035-02-13 Tue	58	—	unknown	03:30–05:45 (good, 2.25 h)	87.1° 09:25	10.33	32%	102.3°
2035-02-14 Wed	59	—	unknown	03:25–05:45 (good, 2.33 h)	87.1° 09:20	10.29	43%	109.1°
2035-02-15 Thu	60	—	unknown	03:20–05:45 (good, 2.42 h)	87.1° 09:15	10.25	54%	115.0°
2035-02-16 Fri	62	—	unknown	03:15–05:45 (good, 2.5 h)	87.1° 09:10	10.21	66%	119.6°
2035-02-17 Sat	61	—	unknown	03:20–05:40 (good, 2.33 h)	87.1° 09:05	10.17	76%	122.3°
2035-02-18 Sun	61	—	unknown	03:15–05:40 (good, 2.42 h)	87.1° 09:05	10.13	85%	122.8°
2035-02-19 Mon	60	—	unknown	03:15–05:40 (good, 2.42 h)	87.1° 09:00	10.09	92%	121.0°
2035-02-20 Tue	53	—	unknown	03:15–05:40 (good, 2.42 h)	87.1° 08:55	10.05	97%	117.3°
2035-02-21 Wed	49	—	unknown	03:15–05:35 (good, 2.33 h)	87.1° 08:50	10.01	100%	111.9°
2035-02-22 Thu	45	—	unknown	03:20–05:35 (good, 2.25 h)	87.1° 08:45	9.96	100%	105.6°
2035-02-23 Fri	42	—	unknown	03:30–05:35 (good, 2.08 h)	87.1° 08:45	9.92	97%	98.7°
2035-02-24 Sat	39	—	unknown	03:45–05:35 (good, 1.83 h)	87.1° 08:40	9.88	92%	91.7°
2035-02-25 Sun	37	—	unknown	03:55–05:30 (good, 1.58 h)	87.1° 08:35	9.83	86%	84.8°
2035-02-26 Mon	38	—	unknown	03:50–05:30 (good, 1.67 h)	87.1° 08:30	9.79	79%	78.2°
2035-02-27 Tue	40	—	unknown	03:20–05:30 (good, 2.17 h)	87.1° 08:25	9.75	70%	72.2°
2035-02-28 Wed	43	—	unknown	02:55–05:25 (good, 2.5 h)	87.1° 08:25	9.7	61%	66.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-01-30&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.