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: 05-29 (100), 05-30 (100), 05-31 (100), 06-01 (100), 06-02 (100) — by astronomy; check the weather when the night is within four days.

2046-05-29astronomy score per night — click a bar for that night2046-06-27

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-05-29 Tue	100	—	unknown	22:55–03:50 (good, 4.92 h)	87.1° 03:30	4.9	30%	80.4°
2046-05-30 Wed	100	—	unknown	22:55–03:45 (good, 4.83 h)	87.1° 03:25	4.86	21%	85.6°
2046-05-31 Thu	100	—	unknown	22:55–03:45 (good, 4.83 h)	87.1° 03:20	4.83	14%	91.0°
2046-06-01 Fri	100	—	unknown	23:00–03:45 (good, 4.75 h)	87.1° 03:15	4.79	8%	96.6°
2046-06-02 Sat	100	—	unknown	23:00–03:45 (good, 4.75 h)	87.1° 03:15	4.75	3%	101.9°
2046-06-03 Sun	100	—	unknown	23:00–03:45 (good, 4.75 h)	87.1° 03:10	4.72	1%	106.9°
2046-06-04 Mon	100	—	unknown	23:00–03:45 (good, 4.75 h)	87.1° 03:05	4.69	0%	111.2°
2046-06-05 Tue	100	—	unknown	23:00–03:40 (good, 4.67 h)	87.1° 03:00	4.66	2%	114.5°
2046-06-06 Wed	100	—	unknown	23:05–03:40 (good, 4.58 h)	87.1° 02:55	4.63	6%	116.5°
2046-06-07 Thu	100	—	unknown	23:05–03:40 (good, 4.58 h)	87.1° 02:55	4.6	12%	116.9°
2046-06-08 Fri	100	—	unknown	23:05–03:40 (good, 4.58 h)	87.1° 02:50	4.58	21%	115.5°
2046-06-09 Sat	100	—	unknown	23:05–03:40 (good, 4.58 h)	87.1° 02:45	4.55	31%	112.6°
2046-06-10 Sun	100	—	unknown	23:05–03:40 (good, 4.58 h)	87.1° 02:40	4.53	42%	108.3°
2046-06-11 Mon	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:40	4.51	53%	103.0°
2046-06-12 Tue	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:35	4.49	65%	97.0°
2046-06-13 Wed	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:30	4.48	75%	90.6°
2046-06-14 Thu	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:25	4.46	84%	84.3°
2046-06-15 Fri	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:20	4.45	92%	78.2°
2046-06-16 Sat	72	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:20	4.44	97%	72.9°
2046-06-17 Sun	63	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:15	4.43	99%	68.4°
2046-06-18 Mon	58	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:10	4.43	100%	65.2°
2046-06-19 Tue	60	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 02:05	4.42	98%	63.4°
2046-06-20 Wed	65	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 02:00	4.42	94%	63.1°
2046-06-21 Thu	97	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 02:00	4.42	88%	64.2°
2046-06-22 Fri	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:55	4.43	81%	66.5°
2046-06-23 Sat	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:50	4.43	73%	69.8°
2046-06-24 Sun	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:45	4.44	64%	73.9°
2046-06-25 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:45	4.45	55%	78.6°
2046-06-26 Tue	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:40	4.46	45%	83.7°
2046-06-27 Wed	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:35	4.47	36%	89.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-05-29&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.