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: 10-25 (100), 10-26 (100), 10-27 (100), 10-28 (100), 10-29 (100) — by astronomy; check the weather when the night is within four days.

2029-10-20astronomy score per night — click a bar for that night2029-11-18

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-10-20 Sat	47	—	unknown	20:05–02:45 (marginal, 6.67 h)	87.2° 20:25	10.05	98%	58.3°
2029-10-21 Sun	52	—	unknown	20:05–20:10 (good, 0.08 h)	87.2° 20:20	10.09	100%	63.2°
2029-10-22 Mon	61	—	unknown	20:05–21:20 (good, 1.25 h)	87.2° 20:15	10.13	100%	69.0°
2029-10-23 Tue	71	—	unknown	20:05–23:00 (good, 2.92 h)	87.2° 20:10	10.17	98%	75.5°
2029-10-24 Wed	78	—	unknown	20:00–00:00 (good, 4.0 h)	87.2° 20:05	10.21	94%	82.5°
2029-10-25 Thu	100	—	unknown	20:00–01:00 (good, 5.0 h)	87.2° 20:05	10.25	89%	89.7°
2029-10-26 Fri	100	—	unknown	20:00–01:50 (good, 5.83 h)	87.2° 20:00	10.29	83%	97.0°
2029-10-27 Sat	100	—	unknown	20:00–01:55 (good, 5.92 h)	87.2° 19:55	10.32	75%	104.1°
2029-10-28 Sun	100	—	unknown	18:55–01:00 (good, 6.08 h)	87.2° 18:50	10.36	66%	111.0°
2029-10-29 Mon	100	—	unknown	18:55–01:00 (good, 6.08 h)	87.2° 18:50	10.4	56%	117.2°
2029-10-30 Tue	100	—	unknown	18:55–01:00 (good, 6.08 h)	87.2° 18:45	10.44	45%	122.4°
2029-10-31 Wed	100	—	unknown	18:55–01:00 (good, 6.08 h)	87.2° 18:40	10.48	35%	126.0°
2029-11-01 Thu	100	—	unknown	18:50–00:55 (good, 6.08 h)	87.2° 18:35	10.51	25%	127.4°
2029-11-02 Fri	100	—	unknown	18:50–00:50 (good, 6.0 h)	87.2° 18:30	10.55	15%	126.3°
2029-11-03 Sat	100	—	unknown	18:50–00:50 (good, 6.0 h)	87.2° 18:30	10.58	8%	122.5°
2029-11-04 Sun	100	—	unknown	18:50–00:45 (good, 5.92 h)	87.2° 18:25	10.62	3%	116.4°
2029-11-05 Mon	100	—	unknown	18:50–00:40 (good, 5.83 h)	87.2° 18:20	10.65	0%	108.6°
2029-11-06 Tue	100	—	unknown	18:45–00:35 (good, 5.83 h)	87.2° 18:15	10.69	1%	99.9°
2029-11-07 Wed	100	—	unknown	18:45–00:30 (good, 5.75 h)	87.2° 18:10	10.72	4%	90.8°
2029-11-08 Thu	100	—	unknown	18:45–00:30 (good, 5.75 h)	87.2° 18:10	10.75	11%	81.8°
2029-11-09 Fri	100	—	unknown	18:45–00:25 (good, 5.67 h)	87.2° 18:05	10.79	19%	73.4°
2029-11-10 Sat	97	—	unknown	18:45–00:20 (good, 5.58 h)	87.2° 18:00	10.82	28%	66.0°
2029-11-11 Sun	88	—	unknown	18:40–00:15 (good, 5.58 h)	87.2° 17:55	10.85	39%	60.0°
2029-11-12 Mon	81	—	unknown	18:40–00:15 (good, 5.58 h)	87.2° 17:55	10.88	49%	55.5°
2029-11-13 Tue	70	—	unknown	18:40–23:40 (good, 5.0 h)	87.2° 17:50	10.91	59%	53.0°
2029-11-14 Wed	58	—	unknown	18:40–21:30 (good, 2.83 h)	87.2° 17:45	10.94	68%	52.5°
2029-11-15 Thu	48	—	unknown	18:40–00:25 (marginal, 5.75 h)	87.2° 17:40	10.97	77%	54.0°
2029-11-16 Fri	43	—	unknown	18:40–00:15 (marginal, 5.58 h)	87.2° 17:35	11.0	84%	57.2°
2029-11-17 Sat	41	—	unknown	18:40–00:00 (marginal, 5.33 h)	87.2° 17:35	11.02	91%	61.8°
2029-11-18 Sun	43	—	unknown	18:40–23:55 (marginal, 5.25 h)	87.2° 17:30	11.05	95%	67.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-10-20&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.