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: 11-14 (100), 11-15 (100), 11-16 (100), 11-17 (100), 11-18 (100) — by astronomy; check the weather when the night is within four days.

2041-11-14astronomy score per night — click a bar for that night2041-12-13

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2041-11-14 Thu	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.2° 17:45	10.94	57%	114.2°
2041-11-15 Fri	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.2° 17:40	10.97	48%	116.7°
2041-11-16 Sat	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.2° 17:35	11.0	38%	118.1°
2041-11-17 Sun	100	—	unknown	18:40–23:55 (good, 5.25 h)	87.2° 17:35	11.03	29%	118.1°
2041-11-18 Mon	100	—	unknown	18:35–23:50 (good, 5.25 h)	87.2° 17:30	11.05	21%	116.8°
2041-11-19 Tue	100	—	unknown	18:35–23:45 (good, 5.17 h)	87.2° 17:25	11.08	14%	114.3°
2041-11-20 Wed	100	—	unknown	18:35–23:40 (good, 5.08 h)	87.2° 17:20	11.1	8%	110.7°
2041-11-21 Thu	100	—	unknown	18:35–23:40 (good, 5.08 h)	87.2° 17:15	11.13	3%	106.1°
2041-11-22 Fri	100	—	unknown	18:35–23:35 (good, 5.0 h)	87.2° 17:15	11.15	1%	100.8°
2041-11-23 Sat	100	—	unknown	18:35–23:30 (good, 4.92 h)	87.2° 17:10	11.18	0%	94.9°
2041-11-24 Sun	100	—	unknown	18:35–23:25 (good, 4.83 h)	87.2° 17:05	11.2	2%	88.6°
2041-11-25 Mon	100	—	unknown	18:35–23:20 (good, 4.75 h)	87.2° 17:00	11.22	6%	82.4°
2041-11-26 Tue	100	—	unknown	18:35–23:20 (good, 4.75 h)	87.2° 17:00	11.24	12%	76.3°
2041-11-27 Wed	98	—	unknown	18:35–23:15 (good, 4.67 h)	87.2° 16:55	11.26	20%	70.9°
2041-11-28 Thu	90	—	unknown	18:35–23:10 (good, 4.58 h)	87.2° 16:50	11.28	29%	66.4°
2041-11-29 Fri	84	—	unknown	18:35–23:05 (good, 4.5 h)	87.2° 16:45	11.3	40%	63.3°
2041-11-30 Sat	71	—	unknown	18:35–22:40 (good, 4.08 h)	87.2° 16:40	11.32	51%	61.8°
2041-12-01 Sun	59	—	unknown	18:35–22:15 (good, 3.67 h)	87.2° 16:40	11.34	62%	62.1°
2041-12-02 Mon	49	—	unknown	18:35–20:25 (good, 1.83 h)	87.2° 16:35	11.35	73%	64.3°
2041-12-03 Tue	43	—	unknown	18:35–19:35 (good, 1.0 h)	87.2° 16:30	11.37	83%	68.1°
2041-12-04 Wed	41	—	unknown	18:35–19:25 (good, 0.83 h)	87.2° 16:25	11.38	90%	73.1°
2041-12-05 Thu	44	—	unknown	18:35–19:40 (good, 1.08 h)	87.2° 16:20	11.4	96%	79.0°
2041-12-06 Fri	49	—	unknown	18:35–20:15 (good, 1.67 h)	87.2° 16:20	11.41	99%	85.4°
2041-12-07 Sat	56	—	unknown	18:35–20:55 (good, 2.33 h)	87.2° 16:15	11.42	100%	91.9°
2041-12-08 Sun	64	—	unknown	18:35–21:45 (good, 3.17 h)	87.2° 16:10	11.44	98%	98.1°
2041-12-09 Mon	73	—	unknown	18:35–22:00 (good, 3.42 h)	87.2° 16:05	11.45	94%	103.9°
2041-12-10 Tue	91	—	unknown	18:35–22:05 (good, 3.5 h)	87.2° 16:05	11.46	89%	109.0°
2041-12-11 Wed	94	—	unknown	18:35–22:05 (good, 3.5 h)	87.2° 16:00	11.47	82%	113.1°
2041-12-12 Thu	95	—	unknown	18:35–22:05 (good, 3.5 h)	87.2° 15:55	11.47	74%	116.1°
2041-12-13 Fri	95	—	unknown	18:35–22:10 (good, 3.58 h)	87.2° 15:50	11.48	65%	117.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2041-11-14&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.