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: 05-26 (100), 05-27 (100), 05-28 (100), 05-29 (100), 05-30 (100) — by astronomy; check the weather when the night is within four days.

2036-05-26astronomy score per night — click a bar for that night2036-06-24

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-05-26 Mon	100	—	unknown	23:45–03:50 (good, 4.08 h)	87.2° 06:00	5.01	2%	100.1°
2036-05-27 Tue	100	—	unknown	23:40–03:50 (good, 4.17 h)	87.2° 05:55	4.97	6%	107.0°
2036-05-28 Wed	100	—	unknown	23:35–03:50 (good, 4.25 h)	87.2° 05:50	4.93	13%	113.0°
2036-05-29 Thu	100	—	unknown	23:35–03:50 (good, 4.25 h)	87.2° 05:50	4.89	22%	117.6°
2036-05-30 Fri	100	—	unknown	23:35–03:45 (good, 4.17 h)	87.2° 05:45	4.85	33%	120.4°
2036-05-31 Sat	100	—	unknown	23:30–03:45 (good, 4.25 h)	87.2° 05:40	4.81	44%	121.1°
2036-06-01 Sun	100	—	unknown	23:30–03:45 (good, 4.25 h)	87.2° 05:35	4.78	55%	119.7°
2036-06-02 Mon	100	—	unknown	23:30–03:45 (good, 4.25 h)	87.2° 05:35	4.74	66%	116.6°
2036-06-03 Tue	100	—	unknown	23:30–03:45 (good, 4.25 h)	87.2° 05:30	4.71	76%	112.0°
2036-06-04 Wed	89	—	unknown	23:30–03:40 (good, 4.17 h)	87.2° 05:25	4.68	84%	106.5°
2036-06-05 Thu	83	—	unknown	23:35–03:40 (good, 4.08 h)	87.2° 05:20	4.65	91%	100.3°
2036-06-06 Fri	73	—	unknown	23:45–03:40 (good, 3.92 h)	87.2° 05:15	4.62	96%	93.8°
2036-06-07 Sat	65	—	unknown	00:15–03:40 (good, 3.42 h)	87.2° 05:15	4.59	99%	87.3°
2036-06-08 Sun	59	—	unknown	00:45–03:40 (good, 2.92 h)	87.2° 05:10	4.57	100%	81.0°
2036-06-09 Mon	55	—	unknown	01:05–03:40 (good, 2.58 h)	87.2° 05:05	4.54	99%	75.1°
2036-06-10 Tue	53	—	unknown	00:55–03:40 (good, 2.75 h)	87.2° 05:00	4.52	96%	69.8°
2036-06-11 Wed	55	—	unknown	23:50–03:40 (good, 3.83 h)	87.2° 04:55	4.5	91%	65.4°
2036-06-12 Thu	76	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:55	4.49	85%	62.0°
2036-06-13 Fri	86	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:50	4.47	78%	59.8°
2036-06-14 Sat	91	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:45	4.46	70%	59.0°
2036-06-15 Sun	95	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:40	4.45	61%	59.7°
2036-06-16 Mon	99	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:40	4.44	51%	61.9°
2036-06-17 Tue	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:35	4.43	41%	65.4°
2036-06-18 Wed	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:30	4.43	31%	70.2°
2036-06-19 Thu	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 04:25	4.42	22%	76.0°
2036-06-20 Fri	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:20	4.42	14%	82.6°
2036-06-21 Sat	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:20	4.42	7%	89.7°
2036-06-22 Sun	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:15	4.43	2%	97.1°
2036-06-23 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:10	4.43	0%	104.3°
2036-06-24 Tue	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.2° 04:05	4.44	1%	110.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-05-26&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.