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: 12-18 (85), 12-17 (84), 12-19 (84), 12-20 (82), 12-16 (81) — by astronomy; check the weather when the night is within four days.

2035-12-12astronomy score per night — click a bar for that night2036-01-10

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-12-12 Wed	45	—	unknown	18:35–20:05 (good, 1.5 h)	87.3° 15:55	11.47	93%	84.7°
2035-12-13 Thu	51	—	unknown	18:35–20:40 (good, 2.08 h)	87.3° 15:55	11.48	98%	92.5°
2035-12-14 Fri	58	—	unknown	18:35–21:25 (good, 2.83 h)	87.3° 15:50	11.48	100%	100.3°
2035-12-15 Sat	66	—	unknown	18:35–21:40 (good, 3.08 h)	87.3° 15:45	11.49	99%	107.7°
2035-12-16 Sun	81	—	unknown	18:35–21:45 (good, 3.17 h)	87.3° 15:40	11.5	94%	114.0°
2035-12-17 Mon	84	—	unknown	18:35–21:45 (good, 3.17 h)	87.3° 15:35	11.5	88%	118.7°
2035-12-18 Tue	85	—	unknown	18:35–21:45 (good, 3.17 h)	87.3° 15:35	11.5	79%	121.4°
2035-12-19 Wed	84	—	unknown	18:35–21:50 (good, 3.25 h)	87.3° 15:30	11.51	69%	121.8°
2035-12-20 Thu	82	—	unknown	18:35–21:45 (good, 3.17 h)	87.3° 15:25	11.51	58%	120.2°
2035-12-21 Fri	79	—	unknown	18:35–21:40 (good, 3.08 h)	87.3° 15:20	11.51	47%	116.8°
2035-12-22 Sat	77	—	unknown	18:35–21:35 (good, 3.0 h)	87.3° 15:15	11.51	37%	112.1°
2035-12-23 Sun	74	—	unknown	18:40–21:35 (good, 2.92 h)	87.3° 15:15	11.51	28%	106.6°
2035-12-24 Mon	72	—	unknown	18:40–21:30 (good, 2.83 h)	87.3° 15:10	11.5	19%	100.5°
2035-12-25 Tue	70	—	unknown	18:40–21:25 (good, 2.75 h)	87.3° 15:05	11.5	12%	94.1°
2035-12-26 Wed	68	—	unknown	18:40–21:20 (good, 2.67 h)	87.3° 15:00	11.5	7%	87.7°
2035-12-27 Thu	67	—	unknown	18:40–21:20 (good, 2.67 h)	87.3° 15:00	11.49	3%	81.5°
2035-12-28 Fri	65	—	unknown	18:40–21:15 (good, 2.58 h)	87.3° 14:55	11.49	0%	75.5°
2035-12-29 Sat	63	—	unknown	18:40–21:10 (good, 2.5 h)	87.3° 14:50	11.48	0%	70.1°
2035-12-30 Sun	60	—	unknown	18:40–21:05 (good, 2.42 h)	87.3° 14:45	11.47	2%	65.5°
2035-12-31 Mon	56	—	unknown	18:45–21:00 (good, 2.25 h)	87.3° 14:40	11.46	5%	61.8°
2036-01-01 Tue	53	—	unknown	18:45–21:00 (good, 2.25 h)	87.3° 14:40	11.45	10%	59.3°
2036-01-02 Wed	48	—	unknown	18:45–20:55 (good, 2.17 h)	87.3° 14:35	11.44	16%	58.2°
2036-01-03 Thu	43	—	unknown	18:45–20:40 (good, 1.92 h)	87.3° 14:30	11.43	23%	58.7°
2036-01-04 Fri	37	—	unknown	18:45–20:30 (good, 1.75 h)	87.3° 14:25	11.42	32%	60.7°
2036-01-05 Sat	31	—	unknown	18:45–20:20 (good, 1.58 h)	87.3° 14:20	11.41	42%	64.2°
2036-01-06 Sun	27	—	unknown	18:45–20:10 (good, 1.42 h)	87.3° 14:20	11.39	52%	69.1°
2036-01-07 Mon	23	—	unknown	18:50–19:40 (good, 0.83 h)	87.3° 14:15	11.38	62%	75.0°
2036-01-08 Tue	22	—	unknown	18:50–19:15 (good, 0.42 h)	87.3° 14:10	11.36	73%	81.8°
2036-01-09 Wed	21	—	unknown	18:50–19:15 (good, 0.42 h)	87.3° 14:05	11.35	82%	89.2°
2036-01-10 Thu	22	—	unknown	18:50–19:35 (good, 0.75 h)	87.3° 14:05	11.33	90%	96.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-12-12&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.