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: 11-23 (100), 11-24 (100), 11-25 (100), 11-26 (100), 11-27 (100) — by astronomy; check the weather when the night is within four days.

2029-11-18astronomy score per night — click a bar for that night2029-12-17

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-11-18 Sun	43	—	unknown	18:40–23:55 (marginal, 5.25 h)	87.3° 17:30	11.05	95%	67.4°
2029-11-19 Mon	49	—	unknown	18:35–19:40 (good, 1.08 h)	87.3° 17:25	11.08	98%	73.8°
2029-11-20 Tue	57	—	unknown	18:35–20:40 (good, 2.08 h)	87.3° 17:20	11.1	100%	80.7°
2029-11-21 Wed	68	—	unknown	18:35–21:30 (good, 2.92 h)	87.3° 17:15	11.13	100%	88.0°
2029-11-22 Thu	80	—	unknown	18:35–22:25 (good, 3.83 h)	87.3° 17:15	11.15	97%	95.3°
2029-11-23 Fri	100	—	unknown	18:35–23:00 (good, 4.42 h)	87.3° 17:10	11.17	93%	102.6°
2029-11-24 Sat	100	—	unknown	18:35–23:05 (good, 4.5 h)	87.3° 17:05	11.2	87%	109.5°
2029-11-25 Sun	100	—	unknown	18:35–23:10 (good, 4.58 h)	87.3° 17:00	11.22	80%	115.9°
2029-11-26 Mon	100	—	unknown	18:35–23:10 (good, 4.58 h)	87.3° 17:00	11.24	71%	121.4°
2029-11-27 Tue	100	—	unknown	18:35–23:10 (good, 4.58 h)	87.3° 16:55	11.26	61%	125.4°
2029-11-28 Wed	100	—	unknown	18:35–23:10 (good, 4.58 h)	87.3° 16:50	11.28	51%	127.5°
2029-11-29 Thu	100	—	unknown	18:35–23:05 (good, 4.5 h)	87.3° 16:45	11.3	40%	127.2°
2029-11-30 Fri	100	—	unknown	18:35–23:00 (good, 4.42 h)	87.3° 16:40	11.32	29%	124.4°
2029-12-01 Sat	100	—	unknown	18:35–23:00 (good, 4.42 h)	87.3° 16:40	11.34	19%	119.2°
2029-12-02 Sun	100	—	unknown	18:35–22:55 (good, 4.33 h)	87.3° 16:35	11.35	11%	112.2°
2029-12-03 Mon	100	—	unknown	18:35–22:50 (good, 4.25 h)	87.3° 16:30	11.37	4%	104.0°
2029-12-04 Tue	100	—	unknown	18:35–22:45 (good, 4.17 h)	87.3° 16:25	11.38	1%	95.0°
2029-12-05 Wed	100	—	unknown	18:35–22:40 (good, 4.08 h)	87.3° 16:20	11.4	0%	85.8°
2029-12-06 Thu	100	—	unknown	18:35–22:40 (good, 4.08 h)	87.3° 16:20	11.41	2%	77.0°
2029-12-07 Fri	100	—	unknown	18:35–22:35 (good, 4.0 h)	87.3° 16:15	11.42	7%	68.9°
2029-12-08 Sat	95	—	unknown	18:35–22:30 (good, 3.92 h)	87.3° 16:10	11.44	14%	62.0°
2029-12-09 Sun	86	—	unknown	18:35–22:25 (good, 3.83 h)	87.3° 16:05	11.45	23%	56.8°
2029-12-10 Mon	73	—	unknown	18:35–22:10 (good, 3.58 h)	87.3° 16:05	11.46	32%	53.5°
2029-12-11 Tue	61	—	unknown	18:35–22:00 (good, 3.42 h)	87.3° 16:00	11.47	42%	52.3°
2029-12-12 Wed	51	—	unknown	18:35–21:45 (good, 3.17 h)	87.3° 15:55	11.47	52%	53.3°
2029-12-13 Thu	42	—	unknown	18:35–20:00 (good, 1.42 h)	87.3° 15:50	11.48	61%	56.0°
2029-12-14 Fri	36	—	unknown	18:35–19:05 (good, 0.5 h)	87.3° 15:45	11.49	70%	60.3°
2029-12-15 Sat	34	—	unknown	18:35–18:40 (good, 0.08 h)	87.3° 15:45	11.49	79%	65.7°
2029-12-16 Sun	33	—	unknown	18:35–18:45 (good, 0.17 h)	87.3° 15:40	11.5	86%	72.0°
2029-12-17 Mon	35	—	unknown	18:35–19:05 (good, 0.5 h)	87.3° 15:35	11.5	92%	78.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-11-18&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.