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: 04-08 (56), 04-07 (51), 04-06 (47), 03-23 (45), 03-24 (45) — by astronomy; check the weather when the night is within four days.

2048-03-10astronomy score per night — click a bar for that night2048-04-08

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2048-03-10 Tue	33	—	unknown	03:50–05:10 (good, 1.33 h)	87.2° 10:05	9.19	15%	60.8°
2048-03-11 Wed	35	—	unknown	03:45–05:05 (good, 1.33 h)	87.2° 10:00	9.14	8%	56.1°
2048-03-12 Thu	37	—	unknown	03:40–05:05 (good, 1.42 h)	87.2° 09:55	9.09	3%	53.4°
2048-03-13 Fri	38	—	unknown	03:35–05:05 (good, 1.5 h)	87.2° 09:50	9.04	1%	52.9°
2048-03-14 Sat	38	—	unknown	03:30–05:00 (good, 1.5 h)	87.2° 09:45	8.99	0%	54.6°
2048-03-15 Sun	39	—	unknown	03:30–05:00 (good, 1.5 h)	87.2° 09:45	8.94	2%	58.3°
2048-03-16 Mon	40	—	unknown	03:25–05:00 (good, 1.58 h)	87.2° 09:40	8.89	6%	63.3°
2048-03-17 Tue	40	—	unknown	03:20–04:55 (good, 1.58 h)	87.2° 09:35	8.84	11%	69.3°
2048-03-18 Wed	42	—	unknown	03:15–04:55 (good, 1.67 h)	87.2° 09:30	8.79	18%	75.9°
2048-03-19 Thu	42	—	unknown	03:15–04:55 (good, 1.67 h)	87.2° 09:30	8.74	25%	82.9°
2048-03-20 Fri	42	—	unknown	03:10–04:50 (good, 1.67 h)	87.2° 09:25	8.69	34%	90.0°
2048-03-21 Sat	43	—	unknown	03:05–04:50 (good, 1.75 h)	87.2° 09:20	8.64	43%	97.2°
2048-03-22 Sun	44	—	unknown	03:00–04:45 (good, 1.75 h)	87.2° 09:15	8.58	52%	104.2°
2048-03-23 Mon	45	—	unknown	02:55–04:45 (good, 1.83 h)	87.2° 09:10	8.53	62%	110.8°
2048-03-24 Tue	45	—	unknown	03:00–04:45 (good, 1.75 h)	87.2° 09:10	8.48	71%	116.9°
2048-03-25 Wed	45	—	unknown	02:55–04:40 (good, 1.75 h)	87.2° 09:05	8.42	80%	122.0°
2048-03-26 Thu	45	—	unknown	02:55–04:40 (good, 1.75 h)	87.2° 09:00	8.37	88%	125.6°
2048-03-27 Fri	41	—	unknown	02:55–04:40 (good, 1.75 h)	87.2° 08:55	8.32	94%	127.2°
2048-03-28 Sat	41	—	unknown	02:50–05:35 (good, 1.75 h)	87.2° 09:50	8.26	98%	126.4°
2048-03-29 Sun	41	—	unknown	03:45–05:35 (good, 1.83 h)	87.2° 09:50	8.21	100%	123.0°
2048-03-30 Mon	39	—	unknown	03:45–05:30 (good, 1.75 h)	87.2° 09:45	8.15	99%	117.4°
2048-03-31 Tue	38	—	unknown	03:45–05:30 (good, 1.75 h)	87.2° 09:40	8.1	95%	110.3°
2048-04-01 Wed	36	—	unknown	03:45–05:30 (good, 1.75 h)	87.2° 09:35	8.05	89%	102.1°
2048-04-02 Thu	34	—	unknown	03:40–05:25 (good, 1.75 h)	87.2° 09:35	7.99	80%	93.3°
2048-04-03 Fri	35	—	unknown	03:35–05:25 (good, 1.83 h)	87.2° 09:30	7.93	70%	84.6°
2048-04-04 Sat	36	—	unknown	03:30–05:20 (good, 1.83 h)	87.2° 09:25	7.88	59%	76.2°
2048-04-05 Sun	41	—	unknown	03:20–05:20 (good, 2.0 h)	87.2° 09:20	7.82	48%	68.5°
2048-04-06 Mon	47	—	unknown	03:00–05:20 (good, 2.33 h)	87.2° 09:15	7.77	37%	61.9°
2048-04-07 Tue	51	—	unknown	03:00–05:15 (good, 2.25 h)	87.2° 09:15	7.71	27%	56.9°
2048-04-08 Wed	56	—	unknown	02:55–05:15 (good, 2.33 h)	87.2° 09:10	7.65	18%	53.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2048-03-10&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.