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: 08-22 (100), 08-23 (100), 08-24 (100), 08-25 (100), 08-26 (100) — by astronomy; check the weather when the night is within four days.

2047-08-22astronomy score per night — click a bar for that night2047-09-20

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2047-08-30 Fri	84	—	unknown	21:40–03:25 (good, 5.75 h)	87.1° 21:25	7.49	80%	61.9°
2047-08-31 Sat	63	—	unknown	21:40–01:40 (good, 4.0 h)	87.1° 21:20	7.55	88%	61.3°
2047-09-01 Sun	56	—	unknown	21:35–22:30 (good, 0.92 h)	87.1° 21:15	7.61	94%	62.4°
2047-09-02 Mon	53	—	unknown	21:35–22:05 (good, 0.5 h)	87.1° 21:10	7.66	98%	65.1°
2047-09-03 Tue	55	—	unknown	21:30–22:35 (good, 1.08 h)	87.1° 21:10	7.72	100%	68.9°
2047-09-04 Wed	59	—	unknown	21:30–23:45 (good, 2.25 h)	87.1° 21:05	7.77	100%	73.7°
2047-09-05 Thu	66	—	unknown	21:30–00:15 (good, 2.75 h)	87.1° 21:00	7.83	97%	79.0°
2047-09-06 Fri	77	—	unknown	21:25–01:00 (good, 3.58 h)	87.1° 20:55	7.88	93%	84.7°
2047-09-07 Sat	82	—	unknown	21:25–01:40 (good, 4.25 h)	87.1° 20:55	7.94	88%	90.5°
2047-09-08 Sun	86	—	unknown	21:20–02:20 (good, 5.0 h)	87.1° 20:50	7.99	81%	96.2°
2047-09-09 Mon	100	—	unknown	21:20–02:25 (good, 5.08 h)	87.1° 20:45	8.05	73%	101.6°
2047-09-10 Tue	100	—	unknown	21:20–02:25 (good, 5.08 h)	87.1° 20:40	8.1	64%	106.7°
2047-09-11 Wed	100	—	unknown	21:15–02:25 (good, 5.17 h)	87.1° 20:35	8.16	55%	111.2°
2047-09-12 Thu	100	—	unknown	21:15–02:25 (good, 5.17 h)	87.1° 20:35	8.21	46%	114.8°
2047-09-13 Fri	100	—	unknown	21:10–02:25 (good, 5.25 h)	87.1° 20:30	8.26	36%	117.4°
2047-09-14 Sat	100	—	unknown	21:10–02:20 (good, 5.17 h)	87.1° 20:25	8.32	27%	118.7°
2047-09-15 Sun	100	—	unknown	21:10–02:20 (good, 5.17 h)	87.1° 20:20	8.37	18%	118.5°
2047-09-16 Mon	100	—	unknown	21:05–02:15 (good, 5.17 h)	87.1° 20:15	8.42	10%	116.6°
2047-09-17 Tue	100	—	unknown	21:05–02:15 (good, 5.17 h)	87.1° 20:15	8.47	5%	113.0°
2047-09-18 Wed	100	—	unknown	21:00–02:10 (good, 5.17 h)	87.1° 20:10	8.52	1%	108.1°
2047-09-19 Thu	100	—	unknown	21:00–02:05 (good, 5.08 h)	87.1° 20:05	8.58	0%	101.9°
2047-09-20 Fri	100	—	unknown	21:00–02:00 (good, 5.0 h)	87.1° 20:00	8.63	2%	95.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-08-22&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.