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 Vega: 07-05 (100), 07-06 (100), 07-14 (100), 07-15 (100), 07-16 (100) — by astronomy; check the weather when the night is within four days.

2044-07-05astronomy score per night — click a bar for that night2044-08-03

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2044-07-05 Tue	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.1° 01:00	4.66	84%	76.1°
2044-07-06 Wed	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.1° 00:55	4.69	90%	72.4°
2044-07-07 Thu	99	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:55	4.72	95%	69.3°
2044-07-08 Fri	68	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:50	4.75	98%	67.2°
2044-07-09 Sat	62	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:45	4.79	100%	66.0°
2044-07-10 Sun	63	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:40	4.82	100%	65.9°
2044-07-11 Mon	67	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:40	4.86	97%	67.0°
2044-07-12 Tue	73	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:35	4.9	94%	69.0°
2044-07-13 Wed	78	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:30	4.94	88%	72.1°
2044-07-14 Thu	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:25	4.98	81%	76.0°
2044-07-15 Fri	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:20	5.03	72%	80.5°
2044-07-16 Sat	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:20	5.07	62%	85.6°
2044-07-17 Sun	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:15	5.11	52%	90.9°
2044-07-18 Mon	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:10	5.16	41%	96.4°
2044-07-19 Tue	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:05	5.21	30%	101.7°
2044-07-20 Wed	100	—	unknown	22:55–04:10 (good, 5.25 h)	87.1° 00:00	5.26	20%	106.5°
2044-07-21 Thu	100	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 00:00	5.3	12%	110.5°
2044-07-22 Fri	100	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 23:55	5.35	5%	113.1°
2044-07-23 Sat	100	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 23:50	5.4	1%	114.1°
2044-07-24 Sun	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 23:45	5.45	0%	113.4°
2044-07-25 Mon	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 23:45	5.51	2%	111.0°
2044-07-26 Tue	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 23:40	5.56	7%	107.2°
2044-07-27 Wed	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.1° 23:35	5.61	14%	102.6°
2044-07-28 Thu	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.1° 23:30	5.67	22%	97.5°
2044-07-29 Fri	100	—	unknown	22:40–04:20 (good, 5.67 h)	87.1° 23:25	5.72	32%	92.2°
2044-07-30 Sat	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:25	5.77	42%	86.9°
2044-07-31 Sun	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:20	5.83	52%	82.0°
2044-08-01 Mon	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:15	5.88	62%	77.4°
2044-08-02 Tue	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.1° 23:10	5.94	71%	73.5°
2044-08-03 Wed	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.1° 23:05	5.99	79%	70.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2044-07-05&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.