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: 06-30 (100), 07-01 (100), 07-02 (100), 07-03 (100), 07-04 (100) — by astronomy; check the weather when the night is within four days.

2029-06-29astronomy score per night — click a bar for that night2029-07-28

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-06-29 Fri	76	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 01:25	4.5	84%	64.9°
2029-06-30 Sat	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:20	4.52	76%	69.0°
2029-07-01 Sun	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:20	4.54	67%	73.8°
2029-07-02 Mon	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:15	4.57	58%	79.2°
2029-07-03 Tue	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:10	4.59	48%	84.9°
2029-07-04 Wed	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:05	4.62	39%	90.8°
2029-07-05 Thu	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.1° 01:00	4.65	30%	96.6°
2029-07-06 Fri	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.1° 01:00	4.68	21%	102.3°
2029-07-07 Sat	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.1° 00:55	4.71	14%	107.6°
2029-07-08 Sun	100	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:50	4.74	8%	112.3°
2029-07-09 Mon	100	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:45	4.77	3%	116.1°
2029-07-10 Tue	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:45	4.81	1%	118.6°
2029-07-11 Wed	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:40	4.85	0%	119.6°
2029-07-12 Thu	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:35	4.89	2%	118.9°
2029-07-13 Fri	100	—	unknown	23:00–03:55 (good, 4.92 h)	87.1° 00:30	4.93	6%	116.4°
2029-07-14 Sat	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:25	4.97	13%	112.3°
2029-07-15 Sun	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:25	5.01	21%	106.9°
2029-07-16 Mon	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:20	5.05	31%	100.6°
2029-07-17 Tue	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:15	5.1	42%	93.8°
2029-07-18 Wed	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:10	5.14	54%	86.8°
2029-07-19 Thu	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:05	5.19	65%	79.9°
2029-07-20 Fri	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:05	5.24	76%	73.6°
2029-07-21 Sat	100	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 00:00	5.29	85%	68.1°
2029-07-22 Sun	92	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 23:55	5.34	92%	63.9°
2029-07-23 Mon	63	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 23:50	5.39	97%	61.2°
2029-07-24 Tue	56	—	unknown	22:45–22:55 (good, 0.17 h)	87.1° 23:50	5.44	100%	60.4°
2029-07-25 Wed	56	—	unknown	22:45–23:20 (good, 0.58 h)	87.1° 23:45	5.49	100%	61.3°
2029-07-26 Thu	60	—	unknown	22:45–00:10 (good, 1.42 h)	87.1° 23:40	5.54	98%	63.7°
2029-07-27 Fri	68	—	unknown	22:45–01:40 (good, 2.92 h)	87.1° 23:35	5.59	94%	67.5°
2029-07-28 Sat	75	—	unknown	22:40–02:45 (good, 4.08 h)	87.1° 23:30	5.65	88%	72.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-06-29&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.