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: 10-19 (100), 10-20 (100), 10-21 (100), 10-22 (100), 10-23 (100) — by astronomy; check the weather when the night is within four days.

2035-10-13astronomy score per night — click a bar for that night2035-11-11

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-10-13 Sat	60	—	unknown	20:20–20:25 (good, 0.08 h)	87.2° 20:55	9.73	89%	58.1°
2035-10-14 Sun	60	—	unknown	20:15–20:20 (good, 0.08 h)	87.2° 20:50	9.77	94%	60.3°
2035-10-15 Mon	61	—	unknown	20:15–20:50 (good, 0.58 h)	87.2° 20:45	9.81	98%	64.3°
2035-10-16 Tue	67	—	unknown	20:15–21:50 (good, 1.58 h)	87.2° 20:40	9.86	100%	69.7°
2035-10-17 Wed	73	—	unknown	20:10–23:30 (good, 3.33 h)	87.2° 20:35	9.9	99%	76.2°
2035-10-18 Thu	79	—	unknown	20:10–00:30 (good, 4.33 h)	87.2° 20:35	9.94	96%	83.5°
2035-10-19 Fri	100	—	unknown	20:10–01:30 (good, 5.33 h)	87.2° 20:30	9.98	90%	91.2°
2035-10-20 Sat	100	—	unknown	20:10–02:15 (good, 6.08 h)	87.2° 20:25	10.03	82%	98.8°
2035-10-21 Sun	100	—	unknown	20:05–02:25 (good, 6.33 h)	87.2° 20:20	10.07	72%	106.0°
2035-10-22 Mon	100	—	unknown	20:05–02:25 (good, 6.33 h)	87.2° 20:15	10.11	61%	112.4°
2035-10-23 Tue	100	—	unknown	20:05–02:25 (good, 6.33 h)	87.2° 20:15	10.15	50%	117.4°
2035-10-24 Wed	100	—	unknown	20:00–02:25 (good, 6.42 h)	87.2° 20:10	10.19	38%	120.9°
2035-10-25 Thu	100	—	unknown	20:00–02:25 (good, 6.42 h)	87.2° 20:05	10.23	28%	122.3°
2035-10-26 Fri	100	—	unknown	20:00–02:20 (good, 6.33 h)	87.2° 20:00	10.27	19%	121.7°
2035-10-27 Sat	100	—	unknown	20:00–02:20 (good, 6.33 h)	87.2° 20:00	10.31	11%	119.2°
2035-10-28 Sun	100	—	unknown	18:55–01:15 (good, 6.33 h)	87.2° 18:55	10.35	5%	115.1°
2035-10-29 Mon	100	—	unknown	18:55–01:10 (good, 6.25 h)	87.2° 18:50	10.38	2%	109.8°
2035-10-30 Tue	100	—	unknown	18:55–01:05 (good, 6.17 h)	87.2° 18:45	10.42	0%	103.8°
2035-10-31 Wed	100	—	unknown	18:55–01:00 (good, 6.08 h)	87.2° 18:40	10.46	1%	97.4°
2035-11-01 Thu	100	—	unknown	18:50–01:00 (good, 6.17 h)	87.2° 18:40	10.49	3%	90.8°
2035-11-02 Fri	100	—	unknown	18:50–00:55 (good, 6.08 h)	87.2° 18:35	10.53	8%	84.3°
2035-11-03 Sat	100	—	unknown	18:50–00:50 (good, 6.0 h)	87.2° 18:30	10.57	14%	78.1°
2035-11-04 Sun	100	—	unknown	18:50–00:45 (good, 5.92 h)	87.2° 18:25	10.6	21%	72.4°
2035-11-05 Mon	98	—	unknown	18:50–00:40 (good, 5.83 h)	87.2° 18:20	10.64	29%	67.3°
2035-11-06 Tue	92	—	unknown	18:45–00:40 (good, 5.92 h)	87.2° 18:20	10.67	38%	63.0°
2035-11-07 Wed	86	—	unknown	18:45–00:35 (good, 5.83 h)	87.2° 18:15	10.7	47%	59.9°
2035-11-08 Thu	75	—	unknown	18:45–00:30 (good, 5.75 h)	87.2° 18:10	10.74	56%	58.1°
2035-11-09 Fri	69	—	unknown	18:45–23:55 (good, 5.17 h)	87.2° 18:05	10.77	66%	57.9°
2035-11-10 Sat	61	—	unknown	18:45–21:45 (good, 3.0 h)	87.2° 18:05	10.8	75%	59.4°
2035-11-11 Sun	55	—	unknown	18:45–20:00 (good, 1.25 h)	87.2° 18:00	10.83	84%	62.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-10-13&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.