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: 03-18 (42), 03-16 (40), 03-17 (40), 03-15 (39), 03-14 (38) — by astronomy; check the weather when the night is within four days.

2029-02-17astronomy score per night — click a bar for that night2029-03-18

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-02-17 Sat	18	—	unknown	05:10–05:40 (good, 0.5 h)	87.2° 11:25	10.15	18%	60.8°
2029-02-18 Sun	19	—	unknown	05:05–05:40 (good, 0.58 h)	87.2° 11:20	10.11	25%	66.1°
2029-02-19 Mon	20	—	unknown	05:05–05:40 (good, 0.58 h)	87.2° 11:20	10.07	34%	72.2°
2029-02-20 Tue	21	—	unknown	05:00–05:40 (good, 0.67 h)	87.2° 11:15	10.03	43%	79.0°
2029-02-21 Wed	22	—	unknown	04:55–05:35 (good, 0.67 h)	87.2° 11:10	9.99	53%	86.2°
2029-02-22 Thu	22	—	unknown	04:50–05:35 (good, 0.75 h)	87.2° 11:05	9.94	63%	93.7°
2029-02-23 Fri	23	—	unknown	04:50–05:35 (good, 0.75 h)	87.2° 11:05	9.9	73%	101.4°
2029-02-24 Sat	23	—	unknown	04:45–05:30 (good, 0.75 h)	87.2° 11:00	9.86	82%	108.9°
2029-02-25 Sun	23	—	unknown	04:50–05:30 (good, 0.67 h)	87.2° 10:55	9.81	89%	115.8°
2029-02-26 Mon	22	—	unknown	04:45–05:30 (good, 0.75 h)	87.2° 10:50	9.77	95%	121.6°
2029-02-27 Tue	22	—	unknown	04:45–05:30 (good, 0.75 h)	87.2° 10:45	9.72	99%	125.5°
2029-02-28 Wed	21	—	unknown	04:40–05:25 (good, 0.75 h)	87.2° 10:45	9.68	100%	126.9°
2029-03-01 Thu	22	—	unknown	04:35–05:25 (good, 0.83 h)	87.2° 10:40	9.63	98%	125.2°
2029-03-02 Fri	23	—	unknown	04:35–05:25 (good, 0.83 h)	87.2° 10:35	9.59	92%	121.0°
2029-03-03 Sat	23	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:30	9.54	85%	114.7°
2029-03-04 Sun	23	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:25	9.5	76%	107.2°
2029-03-05 Mon	23	—	unknown	04:25–05:20 (good, 0.92 h)	87.2° 10:25	9.45	65%	99.1°
2029-03-06 Tue	24	—	unknown	04:20–05:15 (good, 0.92 h)	87.2° 10:20	9.4	54%	90.9°
2029-03-07 Wed	25	—	unknown	04:15–05:15 (good, 1.0 h)	87.2° 10:15	9.35	44%	82.9°
2029-03-08 Thu	28	—	unknown	04:05–05:15 (good, 1.17 h)	87.2° 10:10	9.31	33%	75.3°
2029-03-09 Fri	30	—	unknown	03:55–05:10 (good, 1.25 h)	87.2° 10:10	9.26	24%	68.4°
2029-03-10 Sat	33	—	unknown	03:50–05:10 (good, 1.33 h)	87.2° 10:05	9.21	16%	62.5°
2029-03-11 Sun	36	—	unknown	03:45–05:10 (good, 1.42 h)	87.2° 10:00	9.16	10%	57.8°
2029-03-12 Mon	36	—	unknown	03:40–05:05 (good, 1.42 h)	87.2° 09:55	9.11	5%	54.6°
2029-03-13 Tue	37	—	unknown	03:35–05:05 (good, 1.5 h)	87.2° 09:50	9.06	2%	53.2°
2029-03-14 Wed	38	—	unknown	03:35–05:05 (good, 1.5 h)	87.2° 09:50	9.01	0%	53.7°
2029-03-15 Thu	39	—	unknown	03:30–05:00 (good, 1.5 h)	87.2° 09:45	8.96	1%	55.9°
2029-03-16 Fri	40	—	unknown	03:25–05:00 (good, 1.58 h)	87.2° 09:40	8.91	3%	59.7°
2029-03-17 Sat	40	—	unknown	03:20–04:55 (good, 1.58 h)	87.2° 09:35	8.86	7%	64.7°
2029-03-18 Sun	42	—	unknown	03:15–04:55 (good, 1.67 h)	87.2° 09:30	8.81	12%	70.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-02-17&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.