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: 12-02 (89), 12-16 (86), 12-17 (86), 12-18 (85), 12-19 (84) — by astronomy; check the weather when the night is within four days.

2046-12-02astronomy score per night — click a bar for that night2046-12-31

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-12-02 Sun	89	—	unknown	18:35–22:55 (good, 4.33 h)	87.3° 16:35	11.35	27%	59.4°
2046-12-03 Mon	80	—	unknown	18:35–22:50 (good, 4.25 h)	87.2° 16:30	11.37	36%	55.8°
2046-12-04 Tue	66	—	unknown	18:35–22:25 (good, 3.83 h)	87.2° 16:25	11.38	46%	53.9°
2046-12-05 Wed	55	—	unknown	18:35–22:10 (good, 3.58 h)	87.2° 16:25	11.4	56%	53.9°
2046-12-06 Thu	45	—	unknown	18:35–20:10 (good, 1.58 h)	87.2° 16:20	11.41	65%	55.7°
2046-12-07 Fri	39	—	unknown	18:35–19:05 (good, 0.5 h)	87.2° 16:15	11.42	74%	59.0°
2046-12-08 Sat	35	—	unknown	18:35–22:50 (marginal, 4.25 h)	87.2° 16:10	11.43	81%	63.6°
2046-12-09 Sun	35	—	unknown	18:00–22:40 (marginal, 4.67 h)	87.2° 16:10	11.44	88%	69.3°
2046-12-10 Mon	37	—	unknown	18:35–19:10 (good, 0.58 h)	87.2° 16:05	11.45	94%	75.8°
2046-12-11 Tue	42	—	unknown	18:35–19:45 (good, 1.17 h)	87.3° 16:00	11.46	98%	82.9°
2046-12-12 Wed	49	—	unknown	18:35–20:25 (good, 1.83 h)	87.2° 15:55	11.47	100%	90.3°
2046-12-13 Thu	57	—	unknown	18:35–21:15 (good, 2.67 h)	87.2° 15:50	11.48	100%	97.9°
2046-12-14 Fri	66	—	unknown	18:35–21:40 (good, 3.08 h)	87.2° 15:50	11.49	98%	105.3°
2046-12-15 Sat	82	—	unknown	18:35–21:45 (good, 3.17 h)	87.2° 15:45	11.49	93%	112.3°
2046-12-16 Sun	86	—	unknown	18:35–21:50 (good, 3.25 h)	87.3° 15:40	11.5	87%	118.4°
2046-12-17 Mon	86	—	unknown	18:35–21:50 (good, 3.25 h)	87.2° 15:35	11.5	78%	123.1°
2046-12-18 Tue	85	—	unknown	18:35–21:50 (good, 3.25 h)	87.2° 15:30	11.5	69%	125.8°
2046-12-19 Wed	84	—	unknown	18:35–21:50 (good, 3.25 h)	87.2° 15:30	11.51	58%	126.2°
2046-12-20 Thu	82	—	unknown	18:35–21:45 (good, 3.17 h)	87.2° 15:25	11.51	46%	124.2°
2046-12-21 Fri	78	—	unknown	18:35–21:40 (good, 3.08 h)	87.2° 15:20	11.51	35%	119.8°
2046-12-22 Sat	76	—	unknown	18:35–21:35 (good, 3.0 h)	87.2° 15:15	11.51	25%	113.8°
2046-12-23 Sun	74	—	unknown	18:40–21:35 (good, 2.92 h)	87.2° 15:15	11.51	15%	106.4°
2046-12-24 Mon	72	—	unknown	18:40–21:30 (good, 2.83 h)	87.2° 15:10	11.5	8%	98.4°
2046-12-25 Tue	70	—	unknown	18:40–21:25 (good, 2.75 h)	87.3° 15:05	11.5	3%	90.0°
2046-12-26 Wed	68	—	unknown	18:40–21:20 (good, 2.67 h)	87.2° 15:00	11.5	0%	81.7°
2046-12-27 Thu	66	—	unknown	18:40–21:15 (good, 2.58 h)	87.2° 14:55	11.49	0%	74.0°
2046-12-28 Fri	64	—	unknown	18:40–21:15 (good, 2.58 h)	87.2° 14:55	11.48	3%	67.0°
2046-12-29 Sat	60	—	unknown	18:40–21:10 (good, 2.5 h)	87.2° 14:50	11.48	7%	61.2°
2046-12-30 Sun	55	—	unknown	18:40–21:05 (good, 2.42 h)	87.3° 14:45	11.47	13%	56.8°
2046-12-31 Mon	47	—	unknown	18:45–20:55 (good, 2.17 h)	87.2° 14:40	11.46	20%	54.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-12-02&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.