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: 08-09 (100), 08-10 (100), 08-21 (100), 08-22 (100), 08-23 (100) — by astronomy; check the weather when the night is within four days.

2046-08-09astronomy score per night — click a bar for that night2046-09-07

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-08-09 Thu	100	—	unknown	22:20–04:40 (good, 6.33 h)	87.1° 22:45	6.31	60%	75.5°
2046-08-10 Fri	100	—	unknown	22:20–04:40 (good, 6.33 h)	87.1° 22:40	6.36	70%	70.6°
2046-08-11 Sat	96	—	unknown	22:15–04:35 (good, 6.33 h)	87.1° 22:40	6.42	79%	66.8°
2046-08-12 Sun	88	—	unknown	22:15–04:35 (good, 6.33 h)	87.1° 22:35	6.48	87%	64.3°
2046-08-13 Mon	80	—	unknown	22:15–03:25 (good, 5.17 h)	87.1° 22:30	6.54	93%	63.1°
2046-08-14 Tue	62	—	unknown	22:10–23:50 (good, 1.67 h)	87.1° 22:25	6.59	97%	63.4°
2046-08-15 Wed	61	—	unknown	22:10–23:10 (good, 1.0 h)	87.1° 22:20	6.65	100%	64.9°
2046-08-16 Thu	63	—	unknown	22:05–23:40 (good, 1.58 h)	87.1° 22:20	6.71	100%	67.6°
2046-08-17 Fri	67	—	unknown	22:05–00:40 (good, 2.58 h)	87.1° 22:15	6.77	98%	71.2°
2046-08-18 Sat	72	—	unknown	22:05–01:20 (good, 3.25 h)	87.1° 22:10	6.82	95%	75.6°
2046-08-19 Sun	77	—	unknown	22:00–01:55 (good, 3.92 h)	87.1° 22:05	6.88	90%	80.5°
2046-08-20 Mon	82	—	unknown	22:00–02:40 (good, 4.67 h)	87.1° 22:00	6.94	84%	85.7°
2046-08-21 Tue	100	—	unknown	21:55–03:20 (good, 5.42 h)	87.1° 22:00	7.0	76%	91.0°
2046-08-22 Wed	100	—	unknown	21:55–03:30 (good, 5.58 h)	87.1° 21:55	7.05	68%	96.4°
2046-08-23 Thu	100	—	unknown	21:55–03:35 (good, 5.67 h)	87.1° 21:50	7.11	58%	101.6°
2046-08-24 Fri	100	—	unknown	21:50–03:35 (good, 5.75 h)	87.1° 21:45	7.17	48%	106.5°
2046-08-25 Sat	100	—	unknown	21:50–03:35 (good, 5.75 h)	87.1° 21:45	7.23	38%	110.7°
2046-08-26 Sun	100	—	unknown	21:45–03:35 (good, 5.83 h)	87.1° 21:40	7.28	28%	114.1°
2046-08-27 Mon	100	—	unknown	21:45–03:30 (good, 5.75 h)	87.1° 21:35	7.34	19%	116.3°
2046-08-28 Tue	100	—	unknown	21:45–03:30 (good, 5.75 h)	87.1° 21:30	7.4	11%	117.0°
2046-08-29 Wed	100	—	unknown	21:40–03:25 (good, 5.75 h)	87.1° 21:25	7.45	5%	115.8°
2046-08-30 Thu	100	—	unknown	21:40–03:20 (good, 5.67 h)	87.1° 21:25	7.51	1%	112.9°
2046-08-31 Fri	100	—	unknown	21:35–03:20 (good, 5.75 h)	87.1° 21:20	7.56	0%	108.3°
2046-09-01 Sat	100	—	unknown	21:35–03:15 (good, 5.67 h)	87.1° 21:15	7.62	2%	102.6°
2046-09-02 Sun	100	—	unknown	21:35–03:10 (good, 5.58 h)	87.1° 21:10	7.68	7%	96.1°
2046-09-03 Mon	100	—	unknown	21:30–03:05 (good, 5.58 h)	87.1° 21:05	7.73	15%	89.4°
2046-09-04 Tue	100	—	unknown	21:30–03:05 (good, 5.58 h)	87.1° 21:05	7.79	24%	82.8°
2046-09-05 Wed	100	—	unknown	21:25–03:00 (good, 5.58 h)	87.1° 21:00	7.84	34%	76.8°
2046-09-06 Thu	100	—	unknown	21:25–02:55 (good, 5.5 h)	87.1° 20:55	7.9	45%	71.6°
2046-09-07 Fri	98	—	unknown	21:25–02:50 (good, 5.42 h)	87.1° 20:50	7.95	56%	67.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-08-09&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.