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: 06-20 (100), 06-21 (100), 06-22 (100), 06-23 (100), 06-24 (100) — by astronomy; check the weather when the night is within four days.

2033-06-20astronomy score per night — click a bar for that night2033-07-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-06-20 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 02:00	4.42	39%	88.2°
2033-06-21 Tue	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:55	4.42	28%	95.9°
2033-06-22 Wed	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:55	4.43	19%	103.4°
2033-06-23 Thu	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:50	4.43	11%	110.3°
2033-06-24 Fri	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:45	4.44	5%	116.1°
2033-06-25 Sat	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:40	4.45	1%	120.3°
2033-06-26 Sun	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:40	4.46	0%	122.8°
2033-06-27 Mon	100	—	unknown	23:15–03:40 (good, 4.42 h)	87.1° 01:35	4.47	2%	123.2°
2033-06-28 Tue	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 01:30	4.49	5%	121.7°
2033-06-29 Wed	100	—	unknown	23:10–03:40 (good, 4.5 h)	87.1° 01:25	4.5	10%	118.5°
2033-06-30 Thu	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:20	4.52	17%	114.0°
2033-07-01 Fri	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:20	4.54	25%	108.7°
2033-07-02 Sat	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:15	4.57	33%	102.8°
2033-07-03 Sun	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:10	4.59	43%	96.5°
2033-07-04 Mon	100	—	unknown	23:10–03:45 (good, 4.58 h)	87.1° 01:05	4.62	52%	90.0°
2033-07-05 Tue	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.1° 01:00	4.65	62%	83.5°
2033-07-06 Wed	100	—	unknown	23:10–03:50 (good, 4.67 h)	87.1° 01:00	4.68	71%	77.1°
2033-07-07 Thu	100	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:55	4.71	79%	71.0°
2033-07-08 Fri	100	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:50	4.74	87%	65.6°
2033-07-09 Sat	67	—	unknown	23:05–03:50 (good, 4.75 h)	87.1° 00:45	4.78	93%	61.1°
2033-07-10 Sun	55	—	unknown	02:20–03:55 (good, 1.58 h)	87.1° 00:45	4.81	97%	58.0°
2033-07-11 Mon	48	—	unknown	23:05–03:55 (marginal, 4.83 h)	87.1° 00:40	4.85	100%	56.7°
2033-07-12 Tue	49	—	unknown	23:05–03:55 (marginal, 4.83 h)	87.1° 00:35	4.89	99%	57.6°
2033-07-13 Wed	56	—	unknown	23:00–00:20 (good, 1.33 h)	87.1° 00:30	4.93	97%	60.6°
2033-07-14 Thu	68	—	unknown	23:00–02:40 (good, 3.67 h)	87.1° 00:25	4.97	92%	65.5°
2033-07-15 Fri	78	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:25	5.01	84%	71.7°
2033-07-16 Sat	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:20	5.06	75%	79.0°
2033-07-17 Sun	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:15	5.1	64%	86.7°
2033-07-18 Mon	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:10	5.15	53%	94.5°
2033-07-19 Tue	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:05	5.19	41%	102.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-06-20&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.