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 HD 189733: 10-26 (100), 10-27 (100), 10-28 (100), 10-29 (100), 10-30 (100) — by astronomy; check the weather when the night is within four days.

2035-10-26astronomy score per night — click a bar for that night2035-11-24

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-10-26 Fri	100	—	unknown	20:00–00:10 (good, 4.17 h)	71.1° 19:05	10.27	19%	127.5°
2035-10-27 Sat	100	—	unknown	20:00–00:05 (good, 4.08 h)	71.1° 19:00	10.31	11%	118.9°
2035-10-28 Sun	100	—	unknown	18:55–23:00 (good, 4.08 h)	71.1° 17:55	10.35	5%	109.5°
2035-10-29 Mon	100	—	unknown	18:55–23:00 (good, 4.08 h)	71.1° 17:50	10.38	2%	99.7°
2035-10-30 Tue	100	—	unknown	18:55–22:55 (good, 4.0 h)	71.1° 17:50	10.42	0%	89.9°
2035-10-31 Wed	100	—	unknown	18:55–22:50 (good, 3.92 h)	71.1° 17:45	10.46	1%	80.2°
2035-11-01 Thu	100	—	unknown	18:50–22:45 (good, 3.92 h)	71.1° 17:40	10.49	3%	70.9°
2035-11-02 Fri	100	—	unknown	18:50–22:45 (good, 3.92 h)	71.1° 17:35	10.53	8%	62.2°
2035-11-03 Sat	95	—	unknown	18:50–22:40 (good, 3.83 h)	71.1° 17:30	10.57	14%	54.4°
2035-11-04 Sun	86	—	unknown	18:50–22:35 (good, 3.75 h)	71.1° 17:30	10.6	21%	47.7°
2035-11-05 Mon	77	—	unknown	18:50–22:30 (good, 3.67 h)	71.1° 17:25	10.64	29%	42.8°
2035-11-06 Tue	66	—	unknown	18:45–22:25 (good, 3.67 h)	71.1° 17:20	10.67	38%	40.3°
2035-11-07 Wed	54	—	unknown	18:45–22:05 (good, 3.33 h)	71.1° 17:15	10.7	47%	40.5°
2035-11-08 Thu	45	—	unknown	18:45–21:30 (good, 2.75 h)	71.1° 17:15	10.74	56%	43.6°
2035-11-09 Fri	39	—	unknown	18:45–20:10 (good, 1.42 h)	71.1° 17:10	10.77	66%	49.1°
2035-11-10 Sat	36	—	unknown	18:45–19:30 (good, 0.75 h)	71.1° 17:05	10.8	75%	56.5°
2035-11-11 Sun	35	—	unknown	18:45–19:25 (good, 0.67 h)	71.1° 17:00	10.83	84%	65.3°
2035-11-12 Mon	38	—	unknown	18:40–19:45 (good, 1.08 h)	71.1° 16:55	10.86	91%	75.2°
2035-11-13 Tue	43	—	unknown	18:40–20:20 (good, 1.67 h)	71.1° 16:55	10.89	96%	85.7°
2035-11-14 Wed	50	—	unknown	18:40–21:05 (good, 2.42 h)	71.1° 16:50	10.92	99%	96.6°
2035-11-15 Thu	59	—	unknown	18:40–21:30 (good, 2.83 h)	71.1° 16:45	10.95	100%	107.6°
2035-11-16 Fri	67	—	unknown	18:40–21:35 (good, 2.92 h)	71.1° 16:40	10.98	97%	118.2°
2035-11-17 Sat	75	—	unknown	18:40–21:35 (good, 2.92 h)	71.1° 16:35	11.01	92%	127.7°
2035-11-18 Sun	76	—	unknown	18:40–21:30 (good, 2.83 h)	71.1° 16:35	11.04	84%	135.1°
2035-11-19 Mon	78	—	unknown	18:35–21:30 (good, 2.92 h)	71.1° 16:30	11.06	75%	139.3°
2035-11-20 Tue	76	—	unknown	18:35–21:30 (good, 2.92 h)	71.1° 16:25	11.09	64%	139.4°
2035-11-21 Wed	74	—	unknown	18:35–21:30 (good, 2.92 h)	71.1° 16:20	11.11	53%	135.6°
2035-11-22 Thu	72	—	unknown	18:35–21:25 (good, 2.83 h)	71.1° 16:20	11.14	42%	129.0°
2035-11-23 Fri	71	—	unknown	18:35–21:20 (good, 2.75 h)	71.1° 16:15	11.16	32%	120.8°
2035-11-24 Sat	69	—	unknown	18:35–21:15 (good, 2.67 h)	71.1° 16:10	11.19	22%	111.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-10-26&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.