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: 10-22 (100), 10-23 (100), 10-24 (100), 10-25 (100), 10-26 (100) — by astronomy; check the weather when the night is within four days.

2030-10-22astronomy score per night — click a bar for that night2030-11-20

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2030-10-22 Tue	100	—	unknown	20:05–02:35 (good, 6.5 h)	87.2° 20:15	10.12	19%	127.7°
2030-10-23 Wed	100	—	unknown	20:05–02:30 (good, 6.42 h)	87.2° 20:10	10.16	11%	126.7°
2030-10-24 Thu	100	—	unknown	20:00–02:30 (good, 6.5 h)	87.2° 20:10	10.2	5%	123.3°
2030-10-25 Fri	100	—	unknown	20:00–02:25 (good, 6.42 h)	87.2° 20:05	10.24	1%	117.7°
2030-10-26 Sat	100	—	unknown	20:00–02:20 (good, 6.33 h)	87.2° 20:00	10.28	0%	110.5°
2030-10-27 Sun	100	—	unknown	19:00–01:15 (good, 6.25 h)	87.2° 18:55	10.32	2%	102.1°
2030-10-28 Mon	100	—	unknown	18:55–01:15 (good, 6.33 h)	87.2° 18:55	10.35	6%	93.1°
2030-10-29 Tue	100	—	unknown	18:55–01:10 (good, 6.25 h)	87.2° 18:50	10.39	13%	84.0°
2030-10-30 Wed	100	—	unknown	18:55–01:05 (good, 6.17 h)	87.2° 18:45	10.43	22%	75.3°
2030-10-31 Thu	99	—	unknown	18:55–01:00 (good, 6.08 h)	87.2° 18:40	10.47	32%	67.4°
2030-11-01 Fri	90	—	unknown	18:50–00:55 (good, 6.08 h)	87.2° 18:35	10.5	44%	60.7°
2030-11-02 Sat	82	—	unknown	18:50–00:55 (good, 6.08 h)	87.2° 18:35	10.54	55%	55.8°
2030-11-03 Sun	68	—	unknown	18:50–00:20 (good, 5.5 h)	87.2° 18:30	10.57	65%	52.9°
2030-11-04 Mon	57	—	unknown	18:50–18:55 (good, 0.08 h)	87.2° 18:25	10.61	75%	52.3°
2030-11-05 Tue	48	—	unknown	18:50–01:05 (marginal, 6.25 h)	87.2° 18:20	10.64	83%	54.0°
2030-11-06 Wed	44	—	unknown	18:45–00:50 (marginal, 6.08 h)	87.2° 18:15	10.68	90%	57.6°
2030-11-07 Thu	45	—	unknown	18:45–00:40 (marginal, 5.92 h)	87.2° 18:15	10.71	95%	62.6°
2030-11-08 Fri	50	—	unknown	18:45–19:10 (good, 0.42 h)	87.2° 18:10	10.74	98%	68.7°
2030-11-09 Sat	58	—	unknown	18:45–20:40 (good, 1.92 h)	87.2° 18:05	10.78	100%	75.4°
2030-11-10 Sun	69	—	unknown	18:45–21:35 (good, 2.83 h)	87.2° 18:00	10.81	99%	82.6°
2030-11-11 Mon	79	—	unknown	18:45–22:30 (good, 3.75 h)	87.2° 18:00	10.84	97%	89.8°
2030-11-12 Tue	100	—	unknown	18:40–23:25 (good, 4.75 h)	87.2° 17:55	10.87	93%	97.1°
2030-11-13 Wed	100	—	unknown	18:40–23:45 (good, 5.08 h)	87.2° 17:50	10.9	88%	104.1°
2030-11-14 Thu	100	—	unknown	18:40–23:50 (good, 5.17 h)	87.2° 17:45	10.93	81%	110.7°
2030-11-15 Fri	100	—	unknown	18:40–23:50 (good, 5.17 h)	87.2° 17:40	10.96	73%	116.7°
2030-11-16 Sat	100	—	unknown	18:40–23:50 (good, 5.17 h)	87.2° 17:40	10.99	64%	121.8°
2030-11-17 Sun	100	—	unknown	18:40–23:50 (good, 5.17 h)	87.2° 17:35	11.02	54%	125.5°
2030-11-18 Mon	100	—	unknown	18:40–23:50 (good, 5.17 h)	87.2° 17:30	11.04	44%	127.6°
2030-11-19 Tue	100	—	unknown	18:35–23:45 (good, 5.17 h)	87.2° 17:25	11.07	34%	127.5°
2030-11-20 Wed	100	—	unknown	18:35–23:40 (good, 5.08 h)	87.2° 17:20	11.1	24%	125.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2030-10-22&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.