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: 07-31 (100), 08-10 (100), 08-11 (100), 08-12 (100), 08-13 (100) — by astronomy; check the weather when the night is within four days.

2047-07-31astronomy score per night — click a bar for that night2047-08-29

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-07-31 Wed	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:20	5.79	72%	71.9°
2047-08-01 Thu	98	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:20	5.84	82%	67.0°
2047-08-02 Fri	90	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:15	5.9	90%	63.5°
2047-08-03 Sat	81	—	unknown	22:30–03:45 (good, 5.25 h)	87.1° 23:10	5.95	96%	61.6°
2047-08-04 Sun	59	—	unknown	22:30–22:50 (good, 0.33 h)	87.1° 23:05	6.01	99%	61.5°
2047-08-05 Mon	59	—	unknown	22:30–23:10 (good, 0.67 h)	87.1° 23:00	6.07	100%	63.1°
2047-08-06 Tue	64	—	unknown	22:25–00:00 (good, 1.58 h)	87.1° 23:00	6.12	99%	66.2°
2047-08-07 Wed	70	—	unknown	22:25–01:30 (good, 3.08 h)	87.1° 22:55	6.18	95%	70.4°
2047-08-08 Thu	75	—	unknown	22:20–02:15 (good, 3.92 h)	87.1° 22:50	6.24	90%	75.4°
2047-08-09 Fri	80	—	unknown	22:20–03:00 (good, 4.67 h)	87.1° 22:45	6.29	83%	80.8°
2047-08-10 Sat	100	—	unknown	22:20–03:50 (good, 5.5 h)	87.1° 22:45	6.35	75%	86.5°
2047-08-11 Sun	100	—	unknown	22:15–04:10 (good, 5.92 h)	87.1° 22:40	6.41	67%	92.2°
2047-08-12 Mon	100	—	unknown	22:15–04:15 (good, 6.0 h)	87.1° 22:35	6.47	57%	97.8°
2047-08-13 Tue	100	—	unknown	22:15–04:20 (good, 6.08 h)	87.1° 22:30	6.52	48%	103.2°
2047-08-14 Wed	100	—	unknown	22:10–04:20 (good, 6.17 h)	87.1° 22:25	6.58	39%	108.1°
2047-08-15 Thu	100	—	unknown	22:10–04:20 (good, 6.17 h)	87.1° 22:25	6.64	30%	112.3°
2047-08-16 Fri	100	—	unknown	22:05–04:15 (good, 6.17 h)	87.1° 22:20	6.7	21%	115.7°
2047-08-17 Sat	100	—	unknown	22:05–04:15 (good, 6.17 h)	87.1° 22:15	6.75	13%	117.9°
2047-08-18 Sun	100	—	unknown	22:05–04:10 (good, 6.08 h)	87.1° 22:10	6.81	7%	118.7°
2047-08-19 Mon	100	—	unknown	22:00–04:05 (good, 6.08 h)	87.1° 22:05	6.87	3%	117.8°
2047-08-20 Tue	100	—	unknown	22:00–04:05 (good, 6.08 h)	87.1° 22:05	6.93	0%	115.2°
2047-08-21 Wed	100	—	unknown	21:55–04:00 (good, 6.08 h)	87.1° 22:00	6.98	0%	111.1°
2047-08-22 Thu	100	—	unknown	21:55–03:55 (good, 6.0 h)	87.1° 21:55	7.04	3%	105.8°
2047-08-23 Fri	100	—	unknown	21:55–03:50 (good, 5.92 h)	87.1° 21:50	7.1	9%	99.5°
2047-08-24 Sat	100	—	unknown	21:50–03:45 (good, 5.92 h)	87.1° 21:50	7.15	16%	92.7°
2047-08-25 Sun	100	—	unknown	21:50–03:45 (good, 5.92 h)	87.1° 21:45	7.21	26%	85.8°
2047-08-26 Mon	100	—	unknown	21:50–03:40 (good, 5.83 h)	87.1° 21:40	7.27	36%	79.1°
2047-08-27 Tue	100	—	unknown	21:45–03:35 (good, 5.83 h)	87.1° 21:35	7.33	48%	73.1°
2047-08-28 Wed	100	—	unknown	21:45–03:30 (good, 5.75 h)	87.1° 21:30	7.38	59%	67.9°
2047-08-29 Thu	93	—	unknown	21:40–03:25 (good, 5.75 h)	87.1° 21:30	7.44	70%	64.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-07-31&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.