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: 06-29 (100), 06-30 (100), 07-01 (100), 07-02 (100), 07-03 (100) — by astronomy; check the weather when the night is within four days.

2046-06-29astronomy score per night — click a bar for that night2046-07-28

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-06-29 Fri	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.2° 03:50	4.5	19%	74.0°
2046-06-30 Sat	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.2° 03:45	4.52	11%	81.1°
2046-07-01 Sun	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.2° 03:40	4.54	6%	88.6°
2046-07-02 Mon	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.2° 03:35	4.56	2%	96.4°
2046-07-03 Tue	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 03:35	4.59	0%	104.2°
2046-07-04 Wed	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.2° 03:30	4.61	1%	111.5°
2046-07-05 Thu	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.2° 03:25	4.64	4%	117.8°
2046-07-06 Fri	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.2° 03:20	4.67	11%	122.7°
2046-07-07 Sat	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.2° 03:15	4.7	19%	125.3°
2046-07-08 Sun	100	—	unknown	23:05–03:50 (good, 4.75 h)	87.2° 03:15	4.74	29%	125.5°
2046-07-09 Mon	100	—	unknown	23:05–03:50 (good, 4.75 h)	87.2° 03:10	4.77	40%	123.2°
2046-07-10 Tue	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.2° 03:05	4.81	51%	118.7°
2046-07-11 Wed	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.2° 03:00	4.84	62%	112.7°
2046-07-12 Thu	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 02:55	4.88	73%	105.6°
2046-07-13 Fri	100	—	unknown	23:00–03:55 (good, 4.92 h)	87.2° 02:55	4.92	82%	98.0°
2046-07-14 Sat	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.2° 02:50	4.96	90%	90.2°
2046-07-15 Sun	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.2° 02:45	5.01	95%	82.5°
2046-07-16 Mon	73	—	unknown	23:00–04:00 (good, 5.0 h)	87.2° 02:40	5.05	99%	75.2°
2046-07-17 Tue	64	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 02:40	5.09	100%	68.6°
2046-07-18 Wed	57	—	unknown	22:55–00:35 (good, 1.67 h)	87.2° 02:35	5.14	99%	62.9°
2046-07-19 Thu	56	—	unknown	22:55–00:20 (good, 1.42 h)	87.2° 02:30	5.19	96%	58.4°
2046-07-20 Fri	58	—	unknown	22:55–00:40 (good, 1.75 h)	87.2° 02:25	5.23	92%	55.5°
2046-07-21 Sat	65	—	unknown	22:50–01:20 (good, 2.5 h)	87.2° 02:20	5.28	86%	54.3°
2046-07-22 Sun	72	—	unknown	22:50–02:40 (good, 3.83 h)	87.2° 02:20	5.33	79%	54.8°
2046-07-23 Mon	97	—	unknown	22:50–04:10 (good, 5.33 h)	87.2° 02:15	5.38	70%	57.1°
2046-07-24 Tue	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.2° 02:10	5.43	62%	60.8°
2046-07-25 Wed	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.2° 02:05	5.48	52%	65.7°
2046-07-26 Thu	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 02:00	5.53	42%	71.7°
2046-07-27 Fri	100	—	unknown	22:45–04:20 (good, 5.58 h)	87.2° 02:00	5.59	33%	78.4°
2046-07-28 Sat	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.2° 01:55	5.64	23%	85.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-06-29&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.