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 North America Nebula: 11-17 (100), 11-18 (100), 11-19 (100), 11-20 (100), 12-05 (100) — by astronomy; check the weather when the night is within four days.

2047-11-17astronomy score per night — click a bar for that night2047-12-16

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-11-17 Sun	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.2° 17:35	11.01	0%	97.2°
2047-11-18 Mon	100	—	unknown	18:40–23:50 (good, 5.17 h)	87.2° 17:30	11.04	3%	88.1°
2047-11-19 Tue	100	—	unknown	18:35–23:45 (good, 5.17 h)	87.1° 17:25	11.07	8%	79.2°
2047-11-20 Wed	100	—	unknown	18:35–23:45 (good, 5.17 h)	87.2° 17:25	11.09	16%	70.9°
2047-11-21 Thu	94	—	unknown	18:35–23:40 (good, 5.08 h)	87.2° 17:20	11.12	25%	63.8°
2047-11-22 Fri	86	—	unknown	18:35–23:35 (good, 5.0 h)	87.2° 17:15	11.14	35%	58.3°
2047-11-23 Sat	79	—	unknown	18:35–23:15 (good, 4.67 h)	87.2° 17:10	11.17	46%	54.6°
2047-11-24 Sun	66	—	unknown	18:35–23:00 (good, 4.42 h)	87.1° 17:10	11.19	56%	52.9°
2047-11-25 Mon	53	—	unknown	18:35–21:00 (good, 2.42 h)	87.2° 17:05	11.21	65%	53.3°
2047-11-26 Tue	45	—	unknown	18:35–23:45 (marginal, 5.17 h)	87.2° 17:00	11.23	74%	55.7°
2047-11-27 Wed	40	—	unknown	18:35–23:35 (marginal, 5.0 h)	87.2° 16:55	11.25	82%	59.6°
2047-11-28 Thu	39	—	unknown	18:35–23:25 (marginal, 4.83 h)	87.2° 16:50	11.27	89%	64.7°
2047-11-29 Fri	41	—	unknown	18:35–18:45 (good, 0.17 h)	87.1° 16:50	11.29	94%	70.7°
2047-11-30 Sat	45	—	unknown	18:35–19:45 (good, 1.17 h)	87.2° 16:45	11.31	98%	77.3°
2047-12-01 Sun	53	—	unknown	18:35–20:30 (good, 1.92 h)	87.2° 16:40	11.33	100%	84.3°
2047-12-02 Mon	61	—	unknown	18:35–21:15 (good, 2.67 h)	87.2° 16:35	11.35	100%	91.5°
2047-12-03 Tue	72	—	unknown	18:35–22:05 (good, 3.5 h)	87.1° 16:30	11.36	98%	98.7°
2047-12-04 Wed	82	—	unknown	18:35–22:25 (good, 3.83 h)	87.2° 16:30	11.38	95%	105.7°
2047-12-05 Thu	100	—	unknown	18:35–22:30 (good, 3.92 h)	87.2° 16:25	11.39	90%	112.3°
2047-12-06 Fri	100	—	unknown	18:35–22:30 (good, 3.92 h)	87.2° 16:20	11.41	83%	118.1°
2047-12-07 Sat	100	—	unknown	18:35–22:30 (good, 3.92 h)	87.2° 16:15	11.42	74%	122.9°
2047-12-08 Sun	100	—	unknown	18:35–22:35 (good, 4.0 h)	87.1° 16:10	11.43	65%	126.1°
2047-12-09 Mon	100	—	unknown	18:35–22:30 (good, 3.92 h)	87.2° 16:10	11.44	55%	127.3°
2047-12-10 Tue	100	—	unknown	18:35–22:25 (good, 3.83 h)	87.2° 16:05	11.45	44%	126.1°
2047-12-11 Wed	99	—	unknown	18:35–22:20 (good, 3.75 h)	87.2° 16:00	11.46	33%	122.6°
2047-12-12 Thu	97	—	unknown	18:35–22:15 (good, 3.67 h)	87.2° 15:55	11.47	22%	117.0°
2047-12-13 Fri	96	—	unknown	18:35–22:15 (good, 3.67 h)	87.1° 15:55	11.48	14%	109.7°
2047-12-14 Sat	94	—	unknown	18:35–22:10 (good, 3.58 h)	87.2° 15:50	11.48	6%	101.3°
2047-12-15 Sun	92	—	unknown	18:35–22:05 (good, 3.5 h)	87.2° 15:45	11.49	2%	92.3°
2047-12-16 Mon	90	—	unknown	18:35–22:00 (good, 3.42 h)	87.2° 15:40	11.5	0%	83.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-11-17&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.