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: 10-23 (100), 10-24 (100), 10-25 (100), 10-26 (100), 10-27 (100) — by astronomy; check the weather when the night is within four days.

2041-10-23astronomy score per night — click a bar for that night2041-11-21

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2041-10-23 Wed	100	—	unknown	20:05–02:30 (good, 6.42 h)	87.3° 20:10	10.17	1%	113.3°
2041-10-24 Thu	100	—	unknown	20:00–02:25 (good, 6.42 h)	87.2° 20:10	10.21	0%	109.4°
2041-10-25 Fri	100	—	unknown	20:00–02:25 (good, 6.42 h)	87.3° 20:05	10.25	1%	104.6°
2041-10-26 Sat	100	—	unknown	20:00–02:20 (good, 6.33 h)	87.3° 20:00	10.29	3%	99.1°
2041-10-27 Sun	100	—	unknown	19:00–01:15 (good, 6.25 h)	87.3° 18:55	10.33	8%	93.1°
2041-10-28 Mon	100	—	unknown	18:55–01:10 (good, 6.25 h)	87.3° 18:50	10.37	15%	87.0°
2041-10-29 Tue	100	—	unknown	18:55–01:10 (good, 6.25 h)	87.2° 18:50	10.4	23%	80.9°
2041-10-30 Wed	100	—	unknown	18:55–01:05 (good, 6.17 h)	87.3° 18:45	10.44	33%	75.0°
2041-10-31 Thu	95	—	unknown	18:55–01:00 (good, 6.08 h)	87.3° 18:40	10.48	44%	69.8°
2041-11-01 Fri	86	—	unknown	18:50–00:55 (good, 6.08 h)	87.3° 18:35	10.51	55%	65.6°
2041-11-02 Sat	73	—	unknown	18:50–00:30 (good, 5.67 h)	87.2° 18:30	10.55	66%	62.8°
2041-11-03 Sun	66	—	unknown	18:50–22:55 (good, 4.08 h)	87.3° 18:30	10.59	76%	61.7°
2041-11-04 Mon	58	—	unknown	18:50–20:05 (good, 1.25 h)	87.3° 18:25	10.62	86%	62.6°
2041-11-05 Tue	53	—	unknown	18:50–19:15 (good, 0.42 h)	87.3° 18:20	10.66	93%	65.3°
2041-11-06 Wed	54	—	unknown	18:45–19:40 (good, 0.92 h)	87.3° 18:15	10.69	98%	69.7°
2041-11-07 Thu	60	—	unknown	18:45–20:45 (good, 2.0 h)	87.2° 18:10	10.72	100%	75.3°
2041-11-08 Fri	70	—	unknown	18:45–21:35 (good, 2.83 h)	87.3° 18:10	10.76	99%	81.5°
2041-11-09 Sat	79	—	unknown	18:45–22:30 (good, 3.75 h)	87.3° 18:05	10.79	96%	88.0°
2041-11-10 Sun	84	—	unknown	18:45–23:25 (good, 4.67 h)	87.3° 18:00	10.82	91%	94.4°
2041-11-11 Mon	100	—	unknown	18:40–23:50 (good, 5.17 h)	87.3° 17:55	10.85	84%	100.5°
2041-11-12 Tue	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.2° 17:55	10.88	76%	105.9°
2041-11-13 Wed	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.3° 17:50	10.91	67%	110.6°
2041-11-14 Thu	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.3° 17:45	10.94	57%	114.2°
2041-11-15 Fri	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.3° 17:40	10.97	48%	116.8°
2041-11-16 Sat	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.2° 17:35	11.0	38%	118.1°
2041-11-17 Sun	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.2° 17:35	11.03	29%	118.2°
2041-11-18 Mon	100	—	unknown	18:35–23:50 (good, 5.25 h)	87.3° 17:30	11.05	21%	116.9°
2041-11-19 Tue	100	—	unknown	18:35–23:45 (good, 5.17 h)	87.3° 17:25	11.08	14%	114.4°
2041-11-20 Wed	100	—	unknown	18:35–23:40 (good, 5.08 h)	87.3° 17:20	11.1	8%	110.7°
2041-11-21 Thu	100	—	unknown	18:35–23:35 (good, 5.0 h)	87.2° 17:15	11.13	3%	106.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2041-10-23&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.