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: 11-19 (100), 11-20 (100), 11-21 (100), 11-22 (100), 11-23 (100) — by astronomy; check the weather when the night is within four days.

2043-11-11astronomy score per night — click a bar for that night2043-12-10

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-11-11 Wed	67	—	unknown	18:45–23:10 (good, 4.42 h)	87.2° 18:00	10.84	69%	59.0°
2043-11-12 Thu	56	—	unknown	18:40–20:45 (good, 2.08 h)	87.2° 17:55	10.87	79%	59.2°
2043-11-13 Fri	48	—	unknown	18:40–00:30 (marginal, 5.83 h)	87.2° 17:50	10.9	87%	61.4°
2043-11-14 Sat	46	—	unknown	18:40–00:15 (marginal, 5.58 h)	87.2° 17:45	10.93	94%	65.6°
2043-11-15 Sun	49	—	unknown	18:40–19:25 (good, 0.75 h)	87.2° 17:45	10.96	98%	71.4°
2043-11-16 Mon	58	—	unknown	18:40–20:45 (good, 2.08 h)	87.2° 17:40	10.98	100%	78.4°
2043-11-17 Tue	70	—	unknown	18:40–21:40 (good, 3.0 h)	87.2° 17:35	11.01	98%	86.2°
2043-11-18 Wed	82	—	unknown	18:40–22:45 (good, 4.08 h)	87.2° 17:30	11.04	94%	94.0°
2043-11-19 Thu	100	—	unknown	18:35–23:20 (good, 4.75 h)	87.2° 17:25	11.07	87%	101.5°
2043-11-20 Fri	100	—	unknown	18:35–23:25 (good, 4.83 h)	87.2° 17:25	11.09	78%	108.3°
2043-11-21 Sat	100	—	unknown	18:35–23:30 (good, 4.92 h)	87.2° 17:20	11.12	68%	113.9°
2043-11-22 Sun	100	—	unknown	18:35–23:30 (good, 4.92 h)	87.2° 17:15	11.14	57%	118.1°
2043-11-23 Mon	100	—	unknown	18:35–23:30 (good, 4.92 h)	87.2° 17:10	11.16	46%	120.5°
2043-11-24 Tue	100	—	unknown	18:35–23:30 (good, 4.92 h)	87.2° 17:10	11.19	36%	121.3°
2043-11-25 Wed	100	—	unknown	18:35–23:25 (good, 4.83 h)	87.2° 17:05	11.21	27%	120.3°
2043-11-26 Thu	100	—	unknown	18:35–23:20 (good, 4.75 h)	87.2° 17:00	11.23	19%	117.8°
2043-11-27 Fri	100	—	unknown	18:35–23:15 (good, 4.67 h)	87.2° 16:55	11.25	12%	114.1°
2043-11-28 Sat	100	—	unknown	18:35–23:10 (good, 4.58 h)	87.2° 16:50	11.27	6%	109.4°
2043-11-29 Sun	100	—	unknown	18:35–23:10 (good, 4.58 h)	87.2° 16:50	11.29	3%	104.1°
2043-11-30 Mon	100	—	unknown	18:35–23:05 (good, 4.5 h)	87.2° 16:45	11.31	1%	98.3°
2043-12-01 Tue	100	—	unknown	18:35–23:00 (good, 4.42 h)	87.2° 16:40	11.33	0%	92.2°
2043-12-02 Wed	100	—	unknown	18:35–22:55 (good, 4.33 h)	87.2° 16:35	11.35	2%	86.1°
2043-12-03 Thu	100	—	unknown	18:35–22:50 (good, 4.25 h)	87.2° 16:30	11.36	5%	80.0°
2043-12-04 Fri	100	—	unknown	18:35–22:50 (good, 4.25 h)	87.2° 16:30	11.38	10%	74.2°
2043-12-05 Sat	95	—	unknown	18:35–22:45 (good, 4.17 h)	87.2° 16:25	11.39	16%	69.0°
2043-12-06 Sun	92	—	unknown	18:35–22:40 (good, 4.08 h)	87.2° 16:20	11.41	24%	64.5°
2043-12-07 Mon	82	—	unknown	18:35–22:35 (good, 4.0 h)	87.2° 16:15	11.42	33%	61.1°
2043-12-08 Tue	69	—	unknown	18:35–22:15 (good, 3.67 h)	87.2° 16:10	11.43	42%	59.0°
2043-12-09 Wed	57	—	unknown	18:35–22:00 (good, 3.42 h)	87.2° 16:10	11.44	53%	58.6°
2043-12-10 Thu	47	—	unknown	18:35–20:35 (good, 2.0 h)	87.2° 16:05	11.45	64%	60.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-11-11&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.