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.

2032-09-12astronomy score per night — click a bar for that night2032-10-11

night of	weather	overall	best window	highest	dark h	Moon	Moon sep.
2032-09-12 Sun	—	unknown	—	50.2° 14:25	8.24	52%	76.4°
2032-09-13 Mon	—	unknown	—	50.2° 14:20	8.3	62%	89.9°
2032-09-14 Tue	—	unknown	—	50.2° 14:15	8.35	73%	103.8°
2032-09-15 Wed	—	unknown	—	50.2° 14:10	8.4	83%	118.1°
2032-09-16 Thu	—	unknown	—	50.2° 14:10	8.45	91%	132.8°
2032-09-17 Fri	—	unknown	—	50.2° 14:05	8.51	97%	147.5°
2032-09-18 Sat	—	unknown	—	50.2° 14:00	8.56	100%	162.0°
2032-09-19 Sun	—	unknown	—	50.2° 13:55	8.61	100%	172.9°
2032-09-20 Mon	—	unknown	—	50.2° 13:50	8.66	97%	164.9°
2032-09-21 Tue	—	unknown	—	50.2° 13:50	8.71	91%	151.2°
2032-09-22 Wed	—	unknown	—	50.2° 13:45	8.76	83%	137.4°
2032-09-23 Thu	—	unknown	—	50.2° 13:40	8.81	74%	123.9°
2032-09-24 Fri	—	unknown	—	50.2° 13:35	8.86	65%	110.8°
2032-09-25 Sat	—	unknown	—	50.2° 13:35	8.91	55%	98.1°
2032-09-26 Sun	—	unknown	—	50.2° 13:30	8.96	45%	85.8°
2032-09-27 Mon	—	unknown	—	50.2° 13:25	9.01	35%	73.7°
2032-09-28 Tue	—	unknown	—	50.2° 13:20	9.06	26%	61.8°
2032-09-29 Wed	—	unknown	—	50.2° 13:15	9.11	18%	50.1°
2032-09-30 Thu	—	unknown	—	50.2° 13:15	9.16	12%	38.5°
2032-10-01 Fri	—	unknown	—	50.2° 13:10	9.21	6%	27.0°
2032-10-02 Sat	—	unknown	—	50.2° 13:05	9.25	2%	15.8°
2032-10-03 Sun	—	unknown	—	50.2° 13:00	9.3	0%	7.3°
2032-10-04 Mon	—	unknown	—	50.2° 12:55	9.35	0%	12.0°
2032-10-05 Tue	—	unknown	—	50.2° 12:55	9.39	2%	23.1°
2032-10-06 Wed	—	unknown	—	50.2° 12:50	9.44	5%	35.1°
2032-10-07 Thu	—	unknown	—	50.2° 12:45	9.49	11%	47.5°
2032-10-08 Fri	—	unknown	—	50.2° 12:40	9.53	18%	60.2°
2032-10-09 Sat	—	unknown	—	50.2° 12:40	9.58	27%	73.1°
2032-10-10 Sun	—	unknown	—	50.2° 12:35	9.62	37%	86.3°
2032-10-11 Mon	—	unknown	—	50.2° 12:30	9.67	47%	99.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2032-09-12&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.