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: 06-25 (100), 06-26 (100), 06-27 (100), 06-28 (100), 06-29 (100) — by astronomy; check the weather when the night is within four days.

2044-06-25astronomy score per night — click a bar for that night2044-07-24

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2044-06-25 Sat	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:40	4.45	0%	113.8°
2044-06-26 Sun	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:35	4.46	4%	114.0°
2044-06-27 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:35	4.48	9%	112.4°
2044-06-28 Tue	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 01:30	4.49	17%	109.4°
2044-06-29 Wed	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:25	4.51	26%	105.4°
2044-06-30 Thu	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:20	4.53	37%	100.6°
2044-07-01 Fri	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:15	4.55	47%	95.5°
2044-07-02 Sat	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:15	4.58	57%	90.4°
2044-07-03 Sun	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:10	4.6	67%	85.3°
2044-07-04 Mon	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:05	4.63	76%	80.5°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2044-06-25&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.