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: 11-28 (63), 11-29 (61), 11-30 (59), 12-01 (57), 12-02 (52) — by astronomy; check the weather when the night is within four days.

2035-11-28astronomy score per night — click a bar for that night2035-12-27

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-11-28 Wed	63	—	unknown	18:35–21:00 (good, 2.42 h)	71.1° 15:55	11.27	1%	73.6°
2035-11-29 Thu	61	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 15:50	11.29	0%	64.8°
2035-11-30 Fri	59	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 15:45	11.31	1%	56.7°
2035-12-01 Sat	57	—	unknown	18:35–20:50 (good, 2.25 h)	71.1° 15:40	11.33	4%	49.7°
2035-12-02 Sun	52	—	unknown	18:35–20:45 (good, 2.17 h)	71.1° 15:40	11.34	9%	44.2°
2035-12-03 Mon	48	—	unknown	18:35–20:40 (good, 2.08 h)	71.1° 15:35	11.36	15%	41.0°
2035-12-04 Tue	42	—	unknown	18:35–20:30 (good, 1.92 h)	71.1° 15:30	11.38	22%	40.4°
2035-12-05 Wed	36	—	unknown	18:35–20:20 (good, 1.75 h)	71.1° 15:25	11.39	30%	42.6°
2035-12-06 Thu	31	—	unknown	18:35–20:10 (good, 1.58 h)	71.1° 15:25	11.4	39%	47.3°
2035-12-07 Fri	26	—	unknown	18:35–20:00 (good, 1.42 h)	71.1° 15:20	11.42	49%	54.0°
2035-12-08 Sat	23	—	unknown	18:35–19:25 (good, 0.83 h)	71.1° 15:15	11.43	59%	62.1°
2035-12-09 Sun	21	—	unknown	18:35–19:05 (good, 0.5 h)	71.1° 15:10	11.44	69%	71.3°
2035-12-10 Mon	21	—	unknown	18:35–19:05 (good, 0.5 h)	71.1° 15:05	11.45	78%	81.3°
2035-12-11 Tue	22	—	unknown	18:35–19:25 (good, 0.83 h)	71.1° 15:05	11.46	87%	91.9°
2035-12-12 Wed	24	—	unknown	18:35–19:40 (good, 1.08 h)	71.1° 15:00	11.47	93%	102.8°
2035-12-13 Thu	27	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 14:55	11.48	98%	113.6°
2035-12-14 Fri	29	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 14:50	11.48	100%	123.7°
2035-12-15 Sat	28	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 14:45	11.49	99%	132.3°
2035-12-16 Sun	31	—	unknown	18:35–19:40 (good, 1.08 h)	71.1° 14:45	11.5	94%	138.0°
2035-12-17 Mon	32	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 14:40	11.5	88%	139.7°
2035-12-18 Tue	30	—	unknown	18:35–19:40 (good, 1.08 h)	71.1° 14:35	11.5	79%	136.9°
2035-12-19 Wed	29	—	unknown	18:35–19:40 (good, 1.08 h)	71.1° 14:30	11.51	69%	130.8°
2035-12-20 Thu	27	—	unknown	18:35–19:35 (good, 1.0 h)	71.1° 14:30	11.51	58%	122.7°
2035-12-21 Fri	25	—	unknown	18:35–19:30 (good, 0.92 h)	71.1° 14:25	11.51	47%	113.6°
2035-12-22 Sat	24	—	unknown	18:35–19:25 (good, 0.83 h)	71.1° 14:20	11.51	37%	104.0°
2035-12-23 Sun	22	—	unknown	18:40–19:20 (good, 0.67 h)	71.1° 14:15	11.51	28%	94.4°
2035-12-24 Mon	20	—	unknown	18:40–19:20 (good, 0.67 h)	71.1° 14:10	11.5	19%	84.9°
2035-12-25 Tue	19	—	unknown	18:40–19:15 (good, 0.58 h)	71.1° 14:10	11.5	12%	75.7°
2035-12-26 Wed	18	—	unknown	18:40–19:10 (good, 0.5 h)	71.1° 14:05	11.5	7%	66.8°
2035-12-27 Thu	17	—	unknown	18:40–19:05 (good, 0.42 h)	71.1° 14:00	11.49	3%	58.6°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-11-28&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.