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: 03-11 (36), 03-10 (35), 03-08 (33), 03-09 (33), 03-07 (32) — by astronomy; check the weather when the night is within four days.

2035-02-10astronomy score per night — click a bar for that night2035-03-11

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-02-10 Sat	12	—	unknown	05:40–05:50 (good, 0.17 h)	87.2° 12:00	10.45	7%	59.3°
2035-02-11 Sun	12	—	unknown	05:35–05:50 (good, 0.25 h)	87.2° 11:50	10.41	14%	63.3°
2035-02-12 Mon	13	—	unknown	05:35–05:50 (good, 0.25 h)	87.2° 11:50	10.37	22%	68.8°
2035-02-13 Tue	13	—	unknown	05:30–05:45 (good, 0.25 h)	87.2° 11:45	10.33	32%	75.4°
2035-02-14 Wed	14	—	unknown	05:25–05:45 (good, 0.33 h)	87.2° 11:40	10.29	43%	82.7°
2035-02-15 Thu	15	—	unknown	05:20–05:45 (good, 0.42 h)	87.2° 11:35	10.25	54%	90.4°
2035-02-16 Fri	17	—	unknown	05:15–05:45 (good, 0.5 h)	87.2° 11:30	10.21	66%	98.2°
2035-02-17 Sat	16	—	unknown	05:15–05:40 (good, 0.42 h)	87.2° 11:30	10.17	76%	105.6°
2035-02-18 Sun	18	—	unknown	05:10–05:40 (good, 0.5 h)	87.2° 11:25	10.13	85%	112.3°
2035-02-19 Mon	18	—	unknown	05:15–05:40 (good, 0.42 h)	87.2° 11:20	10.09	92%	117.7°
2035-02-20 Tue	17	—	unknown	05:10–05:40 (good, 0.5 h)	87.2° 11:15	10.05	97%	121.5°
2035-02-21 Wed	17	—	unknown	05:10–05:35 (good, 0.42 h)	87.2° 11:15	10.01	100%	123.2°
2035-02-22 Thu	17	—	unknown	05:05–05:35 (good, 0.5 h)	87.2° 11:10	9.96	100%	122.8°
2035-02-23 Fri	18	—	unknown	05:05–05:35 (good, 0.5 h)	87.2° 11:05	9.92	97%	120.3°
2035-02-24 Sat	18	—	unknown	05:00–05:35 (good, 0.58 h)	87.2° 11:00	9.88	92%	116.2°
2035-02-25 Sun	18	—	unknown	05:00–05:30 (good, 0.5 h)	87.2° 10:55	9.83	86%	111.0°
2035-02-26 Mon	17	—	unknown	05:00–05:30 (good, 0.5 h)	87.2° 10:55	9.79	79%	105.1°
2035-02-27 Tue	18	—	unknown	04:55–05:30 (good, 0.58 h)	87.2° 10:50	9.75	70%	98.8°
2035-02-28 Wed	18	—	unknown	04:50–05:25 (good, 0.58 h)	87.2° 10:45	9.7	61%	92.2°
2035-03-01 Thu	20	—	unknown	04:45–05:25 (good, 0.67 h)	87.2° 10:40	9.66	52%	85.7°
2035-03-02 Fri	22	—	unknown	04:35–05:25 (good, 0.83 h)	87.2° 10:35	9.61	42%	79.4°
2035-03-03 Sat	23	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:35	9.56	33%	73.3°
2035-03-04 Sun	25	—	unknown	04:20–05:20 (good, 1.0 h)	87.2° 10:30	9.52	24%	67.8°
2035-03-05 Mon	28	—	unknown	04:10–05:20 (good, 1.17 h)	87.2° 10:25	9.47	17%	63.0°
2035-03-06 Tue	31	—	unknown	04:05–05:15 (good, 1.17 h)	87.2° 10:20	9.42	10%	59.3°
2035-03-07 Wed	32	—	unknown	04:00–05:15 (good, 1.25 h)	87.2° 10:20	9.38	5%	57.1°
2035-03-08 Thu	33	—	unknown	04:00–05:15 (good, 1.25 h)	87.2° 10:15	9.33	1%	56.8°
2035-03-09 Fri	33	—	unknown	03:55–05:10 (good, 1.25 h)	87.2° 10:10	9.28	0%	58.4°
2035-03-10 Sat	35	—	unknown	03:50–05:10 (good, 1.33 h)	87.2° 10:05	9.23	1%	62.0°
2035-03-11 Sun	36	—	unknown	03:45–05:10 (good, 1.42 h)	87.2° 10:00	9.18	5%	67.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-02-10&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.