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: 11-19 (77), 11-20 (72), 11-21 (66), 11-22 (59), 11-23 (50) — by astronomy; check the weather when the night is within four days.

2036-11-19astronomy score per night — click a bar for that night2036-12-18

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-11-19 Wed	77	—	unknown	18:35–21:35 (good, 3.0 h)	71.1° 16:25	11.08	4%	57.0°
2036-11-20 Thu	72	—	unknown	18:35–21:30 (good, 2.92 h)	71.1° 16:25	11.11	9%	49.9°
2036-11-21 Fri	66	—	unknown	18:35–21:25 (good, 2.83 h)	71.1° 16:20	11.13	15%	44.8°
2036-11-22 Sat	59	—	unknown	18:35–21:20 (good, 2.75 h)	71.1° 16:15	11.16	23%	42.1°
2036-11-23 Sun	50	—	unknown	18:35–21:05 (good, 2.5 h)	71.1° 16:10	11.18	32%	42.2°
2036-11-24 Mon	43	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 16:05	11.2	40%	44.9°
2036-11-25 Tue	37	—	unknown	18:35–20:45 (good, 2.17 h)	71.1° 16:05	11.23	50%	49.8°
2036-11-26 Wed	33	—	unknown	18:35–20:00 (good, 1.42 h)	71.1° 16:00	11.25	59%	56.3°
2036-11-27 Thu	29	—	unknown	18:35–19:30 (good, 0.92 h)	71.1° 15:55	11.27	68%	64.0°
2036-11-28 Fri	28	—	unknown	18:35–19:20 (good, 0.75 h)	71.1° 15:50	11.29	77%	72.5°
2036-11-29 Sat	28	—	unknown	18:35–19:25 (good, 0.83 h)	71.1° 15:45	11.31	85%	81.6°
2036-11-30 Sun	30	—	unknown	18:35–19:50 (good, 1.25 h)	71.1° 15:45	11.32	92%	91.2°
2036-12-01 Mon	34	—	unknown	18:35–20:20 (good, 1.75 h)	71.1° 15:40	11.34	96%	101.0°
2036-12-02 Tue	38	—	unknown	18:35–20:25 (good, 1.83 h)	71.1° 15:35	11.36	99%	110.8°
2036-12-03 Wed	42	—	unknown	18:35–20:25 (good, 1.83 h)	71.1° 15:30	11.37	100%	120.1°
2036-12-04 Thu	42	—	unknown	18:35–20:25 (good, 1.83 h)	71.1° 15:30	11.39	98%	128.4°
2036-12-05 Fri	46	—	unknown	18:35–20:20 (good, 1.75 h)	71.1° 15:25	11.4	93%	134.7°
2036-12-06 Sat	47	—	unknown	18:35–20:20 (good, 1.75 h)	71.1° 15:20	11.41	86%	137.9°
2036-12-07 Sun	46	—	unknown	18:35–20:20 (good, 1.75 h)	71.1° 15:15	11.43	77%	137.2°
2036-12-08 Mon	44	—	unknown	18:35–20:20 (good, 1.75 h)	71.1° 15:10	11.44	66%	132.8°
2036-12-09 Tue	42	—	unknown	18:35–20:15 (good, 1.67 h)	71.1° 15:10	11.45	55%	125.7°
2036-12-10 Wed	41	—	unknown	18:35–20:10 (good, 1.58 h)	71.1° 15:05	11.46	44%	117.0°
2036-12-11 Thu	39	—	unknown	18:35–20:05 (good, 1.5 h)	71.1° 15:00	11.47	33%	107.4°
2036-12-12 Fri	38	—	unknown	18:35–20:00 (good, 1.42 h)	71.1° 14:55	11.48	23%	97.4°
2036-12-13 Sat	36	—	unknown	18:35–20:00 (good, 1.42 h)	71.1° 14:50	11.48	15%	87.4°
2036-12-14 Sun	34	—	unknown	18:35–19:55 (good, 1.33 h)	71.1° 14:50	11.49	8%	77.6°
2036-12-15 Mon	34	—	unknown	18:35–19:50 (good, 1.25 h)	71.1° 14:45	11.49	3%	68.2°
2036-12-16 Tue	32	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 14:40	11.5	1%	59.6°
2036-12-17 Wed	30	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 14:35	11.5	0%	52.2°
2036-12-18 Thu	29	—	unknown	18:35–19:40 (good, 1.08 h)	71.1° 14:35	11.5	2%	46.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-11-19&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.