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 V1057 Cyg: 03-24 (46), 03-25 (46), 03-22 (45), 03-21 (44), 03-23 (44) — by astronomy; check the weather when the night is within four days.

2045-02-24astronomy score per night — click a bar for that night2045-03-25

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2045-02-24 Fri	23	—	unknown	04:45–05:30 (good, 0.75 h)	87.3° 11:00	9.85	53%	85.8°
2045-02-25 Sat	25	—	unknown	04:40–05:30 (good, 0.83 h)	87.3° 10:55	9.81	64%	93.5°
2045-02-26 Sun	25	—	unknown	04:35–05:30 (good, 0.92 h)	87.2° 10:50	9.76	74%	101.3°
2045-02-27 Mon	24	—	unknown	04:45–05:25 (good, 0.67 h)	87.2° 10:45	9.72	84%	108.7°
2045-02-28 Tue	22	—	unknown	04:40–05:25 (good, 0.75 h)	87.2° 10:45	9.67	92%	115.2°
2045-03-01 Wed	23	—	unknown	04:35–05:25 (good, 0.83 h)	87.3° 10:40	9.63	97%	120.2°
2045-03-02 Thu	23	—	unknown	04:35–05:25 (good, 0.83 h)	87.3° 10:35	9.58	100%	123.1°
2045-03-03 Fri	23	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:30	9.54	99%	123.5°
2045-03-04 Sat	23	—	unknown	04:25–05:20 (good, 0.92 h)	87.2° 10:30	9.49	96%	121.5°
2045-03-05 Sun	24	—	unknown	04:25–05:20 (good, 0.92 h)	87.2° 10:25	9.44	91%	117.5°
2045-03-06 Mon	24	—	unknown	04:20–05:15 (good, 0.92 h)	87.3° 10:20	9.4	84%	112.1°
2045-03-07 Tue	24	—	unknown	04:15–05:15 (good, 1.0 h)	87.3° 10:15	9.35	75%	105.9°
2045-03-08 Wed	25	—	unknown	04:15–05:15 (good, 1.0 h)	87.2° 10:10	9.3	66%	99.2°
2045-03-09 Thu	25	—	unknown	04:05–05:10 (good, 1.08 h)	87.2° 10:10	9.25	56%	92.4°
2045-03-10 Fri	27	—	unknown	04:00–05:10 (good, 1.17 h)	87.3° 10:05	9.2	46%	85.7°
2045-03-11 Sat	30	—	unknown	03:55–05:10 (good, 1.25 h)	87.3° 10:00	9.16	37%	79.2°
2045-03-12 Sun	32	—	unknown	03:40–05:05 (good, 1.42 h)	87.2° 09:55	9.11	28%	73.1°
2045-03-13 Mon	36	—	unknown	03:35–05:05 (good, 1.5 h)	87.2° 09:50	9.06	20%	67.6°
2045-03-14 Tue	37	—	unknown	03:35–05:00 (good, 1.42 h)	87.2° 09:50	9.01	13%	62.9°
2045-03-15 Wed	38	—	unknown	03:30–05:00 (good, 1.5 h)	87.3° 09:45	8.96	7%	59.3°
2045-03-16 Thu	40	—	unknown	03:25–05:00 (good, 1.58 h)	87.3° 09:40	8.91	3%	57.0°
2045-03-17 Fri	40	—	unknown	03:20–04:55 (good, 1.58 h)	87.2° 09:35	8.86	1%	56.4°
2045-03-18 Sat	41	—	unknown	03:20–04:55 (good, 1.58 h)	87.2° 09:35	8.8	0%	57.5°
2045-03-19 Sun	42	—	unknown	03:15–04:55 (good, 1.67 h)	87.2° 09:30	8.75	2%	60.3°
2045-03-20 Mon	42	—	unknown	03:10–04:50 (good, 1.67 h)	87.3° 09:25	8.7	5%	64.7°
2045-03-21 Tue	44	—	unknown	03:05–04:50 (good, 1.75 h)	87.3° 09:20	8.65	11%	70.4°
2045-03-22 Wed	45	—	unknown	03:00–04:50 (good, 1.83 h)	87.2° 09:15	8.6	18%	76.9°
2045-03-23 Thu	44	—	unknown	03:00–04:45 (good, 1.75 h)	87.2° 09:15	8.54	27%	84.1°
2045-03-24 Fri	46	—	unknown	02:55–04:45 (good, 1.83 h)	87.3° 09:10	8.49	38%	91.7°
2045-03-25 Sat	46	—	unknown	02:50–05:40 (good, 1.83 h)	87.3° 10:05	8.44	49%	99.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2045-02-24&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.