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

2043-01-24astronomy score per night — click a bar for that night2043-02-22

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-01-24 Sat	25	—	unknown	05:05–06:05 (good, 1.0 h)	87.1° 10:40	11.0	100%	112.5°
2043-01-25 Sun	25	—	unknown	05:05–06:05 (good, 1.0 h)	87.1° 10:35	10.98	99%	110.5°
2043-01-26 Mon	24	—	unknown	05:05–06:05 (good, 1.0 h)	87.1° 10:35	10.95	97%	107.4°
2043-01-27 Tue	23	—	unknown	05:00–06:05 (good, 1.08 h)	87.1° 10:30	10.92	92%	103.5°
2043-01-28 Wed	24	—	unknown	05:00–06:05 (good, 1.08 h)	87.1° 10:25	10.89	86%	99.2°
2043-01-29 Thu	24	—	unknown	04:55–06:00 (good, 1.08 h)	87.1° 10:20	10.86	79%	94.5°
2043-01-30 Fri	26	—	unknown	04:50–06:00 (good, 1.17 h)	87.1° 10:20	10.83	70%	89.8°
2043-01-31 Sat	27	—	unknown	04:40–06:00 (good, 1.33 h)	87.1° 10:15	10.79	62%	85.2°
2043-02-01 Sun	30	—	unknown	04:35–06:00 (good, 1.42 h)	87.1° 10:10	10.76	52%	80.7°
2043-02-02 Mon	33	—	unknown	04:25–06:00 (good, 1.58 h)	87.1° 10:05	10.73	43%	76.6°
2043-02-03 Tue	37	—	unknown	04:15–06:00 (good, 1.75 h)	87.1° 10:00	10.69	34%	73.0°
2043-02-04 Wed	41	—	unknown	04:05–05:55 (good, 1.83 h)	87.1° 10:00	10.66	25%	70.0°
2043-02-05 Thu	45	—	unknown	04:00–05:55 (good, 1.92 h)	87.1° 09:55	10.63	17%	67.9°
2043-02-06 Fri	49	—	unknown	03:55–05:55 (good, 2.0 h)	87.1° 09:50	10.59	10%	66.9°
2043-02-07 Sat	51	—	unknown	03:50–05:55 (good, 2.08 h)	87.1° 09:45	10.55	5%	67.1°
2043-02-08 Sun	53	—	unknown	03:50–05:55 (good, 2.08 h)	87.1° 09:40	10.52	1%	68.5°
2043-02-09 Mon	53	—	unknown	03:45–05:50 (good, 2.08 h)	87.1° 09:40	10.48	0%	71.3°
2043-02-10 Tue	54	—	unknown	03:40–05:50 (good, 2.17 h)	87.1° 09:35	10.44	2%	75.1°
2043-02-11 Wed	55	—	unknown	03:35–05:50 (good, 2.25 h)	87.1° 09:30	10.41	5%	79.9°
2043-02-12 Thu	57	—	unknown	03:30–05:50 (good, 2.33 h)	87.1° 09:25	10.37	12%	85.2°
2043-02-13 Fri	58	—	unknown	03:30–05:45 (good, 2.25 h)	87.1° 09:25	10.33	20%	90.8°
2043-02-14 Sat	59	—	unknown	03:25–05:45 (good, 2.33 h)	87.1° 09:20	10.29	30%	96.4°
2043-02-15 Sun	60	—	unknown	03:20–05:45 (good, 2.42 h)	87.1° 09:15	10.25	41%	101.6°
2043-02-16 Mon	62	—	unknown	03:15–05:45 (good, 2.5 h)	87.1° 09:10	10.21	53%	106.1°
2043-02-17 Tue	62	—	unknown	03:15–05:40 (good, 2.42 h)	87.1° 09:05	10.17	64%	109.6°
2043-02-18 Wed	62	—	unknown	03:20–05:40 (good, 2.33 h)	87.1° 09:05	10.13	74%	112.0°
2043-02-19 Thu	60	—	unknown	03:15–05:40 (good, 2.42 h)	87.1° 09:00	10.09	83%	113.1°
2043-02-20 Fri	53	—	unknown	03:15–05:40 (good, 2.42 h)	87.1° 08:55	10.05	90%	112.8°
2043-02-21 Sat	50	—	unknown	03:15–05:35 (good, 2.33 h)	87.1° 08:50	10.0	96%	111.2°
2043-02-22 Sun	48	—	unknown	03:15–05:35 (good, 2.33 h)	87.1° 08:45	9.96	99%	108.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-01-24&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.