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: 04-02 (45), 03-16 (40), 03-17 (40), 03-18 (40), 03-19 (40) — by astronomy; check the weather when the night is within four days.

2035-03-04astronomy score per night — click a bar for that night2035-04-02

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2035-03-12 Mon	35	—	unknown	03:45–05:05 (good, 1.33 h)	87.2° 10:00	9.13	11%	73.6°
2035-03-13 Tue	37	—	unknown	03:40–05:05 (good, 1.42 h)	87.2° 09:55	9.09	19%	80.9°
2035-03-14 Wed	38	—	unknown	03:35–05:05 (good, 1.5 h)	87.2° 09:50	9.04	29%	88.7°
2035-03-15 Thu	38	—	unknown	03:30–05:00 (good, 1.5 h)	87.2° 09:45	8.99	40%	96.4°
2035-03-16 Fri	40	—	unknown	03:25–05:00 (good, 1.58 h)	87.2° 09:40	8.94	51%	103.9°
2035-03-17 Sat	40	—	unknown	03:25–05:00 (good, 1.58 h)	87.2° 09:40	8.88	62%	110.7°
2035-03-18 Sun	40	—	unknown	03:25–04:55 (good, 1.5 h)	87.2° 09:35	8.83	73%	116.4°
2035-03-19 Mon	40	—	unknown	03:25–04:55 (good, 1.5 h)	87.2° 09:30	8.78	82%	120.6°
2035-03-20 Tue	37	—	unknown	03:20–04:55 (good, 1.58 h)	87.2° 09:25	8.73	90%	122.9°
2035-03-21 Wed	36	—	unknown	03:20–04:50 (good, 1.5 h)	87.2° 09:25	8.68	96%	123.2°
2035-03-22 Thu	35	—	unknown	03:15–04:50 (good, 1.58 h)	87.2° 09:20	8.63	99%	121.4°
2035-03-23 Fri	34	—	unknown	03:15–04:45 (good, 1.5 h)	87.2° 09:15	8.58	100%	117.9°
2035-03-24 Sat	33	—	unknown	04:15–05:45 (good, 1.5 h)	87.2° 10:10	8.52	99%	113.1°
2035-03-25 Sun	31	—	unknown	04:15–05:45 (good, 1.5 h)	87.2° 10:05	8.47	96%	107.3°
2035-03-26 Mon	29	—	unknown	04:15–05:40 (good, 1.42 h)	87.2° 10:05	8.42	91%	101.1°
2035-03-27 Tue	29	—	unknown	04:15–05:40 (good, 1.42 h)	87.2° 10:00	8.36	85%	94.6°
2035-03-28 Wed	30	—	unknown	04:10–05:40 (good, 1.5 h)	87.2° 09:55	8.31	77%	88.0°
2035-03-29 Thu	31	—	unknown	04:00–05:35 (good, 1.58 h)	87.2° 09:50	8.26	69%	81.6°
2035-03-30 Fri	33	—	unknown	03:55–05:35 (good, 1.67 h)	87.2° 09:45	8.2	60%	75.4°
2035-03-31 Sat	35	—	unknown	03:45–05:30 (good, 1.75 h)	87.2° 09:45	8.15	50%	69.7°
2035-04-01 Sun	40	—	unknown	03:25–05:30 (good, 2.08 h)	87.2° 09:40	8.09	41%	64.7°
2035-04-02 Mon	45	—	unknown	03:20–05:30 (good, 2.17 h)	87.2° 09:35	8.04	31%	60.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-03-04&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.