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 V1057 Cyg: 06-19 (100), 06-20 (100), 06-21 (100), 06-22 (100), 07-04 (100) — by astronomy; check the weather when the night is within four days.

2029-06-19astronomy score per night — click a bar for that night2029-07-18

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-06-19 Tue	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.3° 04:25	4.42	56%	123.9°
2029-06-20 Wed	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:25	4.42	67%	118.8°
2029-06-21 Thu	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:20	4.42	78%	112.0°
2029-06-22 Fri	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:15	4.43	87%	104.0°
2029-06-23 Sat	84	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:10	4.43	94%	95.5°
2029-06-24 Sun	76	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:05	4.44	98%	86.8°
2029-06-25 Mon	65	—	unknown	23:15–03:40 (good, 4.42 h)	87.3° 04:05	4.45	100%	78.3°
2029-06-26 Tue	56	—	unknown	23:50–03:40 (good, 3.83 h)	87.3° 04:00	4.46	99%	70.5°
2029-06-27 Wed	52	—	unknown	00:00–02:30 (good, 2.5 h)	87.3° 03:55	4.47	96%	63.6°
2029-06-28 Thu	53	—	unknown	23:10–02:00 (good, 2.83 h)	87.3° 03:50	4.49	91%	58.2°
2029-06-29 Fri	58	—	unknown	23:10–02:35 (good, 3.42 h)	87.3° 03:45	4.5	84%	54.5°
2029-06-30 Sat	87	—	unknown	23:10–03:45 (good, 4.58 h)	87.3° 03:45	4.52	76%	52.7°
2029-07-01 Sun	93	—	unknown	23:10–03:45 (good, 4.58 h)	87.3° 03:40	4.54	67%	53.0°
2029-07-02 Mon	96	—	unknown	23:10–03:45 (good, 4.58 h)	87.3° 03:35	4.57	58%	55.2°
2029-07-03 Tue	99	—	unknown	23:10–03:45 (good, 4.58 h)	87.3° 03:30	4.59	48%	58.9°
2029-07-04 Wed	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.3° 03:30	4.62	39%	63.9°
2029-07-05 Thu	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.3° 03:25	4.65	30%	69.9°
2029-07-06 Fri	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.3° 03:20	4.68	21%	76.5°
2029-07-07 Sat	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.3° 03:15	4.71	14%	83.7°
2029-07-08 Sun	100	—	unknown	23:05–03:50 (good, 4.75 h)	87.3° 03:10	4.74	8%	91.2°
2029-07-09 Mon	100	—	unknown	23:05–03:50 (good, 4.75 h)	87.3° 03:10	4.77	3%	98.9°
2029-07-10 Tue	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.3° 03:05	4.81	1%	106.4°
2029-07-11 Wed	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.3° 03:00	4.85	0%	113.4°
2029-07-12 Thu	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.3° 02:55	4.89	2%	119.6°
2029-07-13 Fri	100	—	unknown	23:00–03:55 (good, 4.92 h)	87.3° 02:50	4.93	6%	124.3°
2029-07-14 Sat	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.3° 02:50	4.97	13%	127.0°
2029-07-15 Sun	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.3° 02:45	5.01	21%	127.1°
2029-07-16 Mon	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.3° 02:40	5.05	31%	124.7°
2029-07-17 Tue	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.3° 02:35	5.1	42%	120.1°
2029-07-18 Wed	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.3° 02:35	5.14	54%	113.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-06-19&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.