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: 11-05 (96), 11-06 (95), 11-07 (94), 11-08 (93), 11-09 (91) — by astronomy; check the weather when the night is within four days.

2045-11-05astronomy score per night — click a bar for that night2045-12-04

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2045-11-05 Sun	96	—	unknown	18:50–22:30 (good, 3.67 h)	71.1° 17:25	10.66	11%	117.3°
2045-11-06 Mon	95	—	unknown	18:45–22:25 (good, 3.67 h)	71.1° 17:20	10.69	5%	107.6°
2045-11-07 Tue	94	—	unknown	18:45–22:20 (good, 3.58 h)	71.1° 17:15	10.72	1%	97.5°
2045-11-08 Wed	93	—	unknown	18:45–22:15 (good, 3.5 h)	71.1° 17:10	10.76	0%	87.3°
2045-11-09 Thu	91	—	unknown	18:45–22:15 (good, 3.5 h)	71.1° 17:05	10.79	1%	77.3°
2045-11-10 Fri	90	—	unknown	18:45–22:10 (good, 3.42 h)	71.1° 17:05	10.82	5%	68.0°
2045-11-11 Sat	90	—	unknown	18:40–22:05 (good, 3.42 h)	71.1° 17:00	10.85	10%	59.5°
2045-11-12 Sun	82	—	unknown	18:40–22:00 (good, 3.33 h)	71.1° 16:55	10.88	17%	52.3°
2045-11-13 Mon	72	—	unknown	18:40–22:00 (good, 3.33 h)	71.1° 16:50	10.91	25%	46.8°
2045-11-14 Tue	61	—	unknown	18:40–21:55 (good, 3.25 h)	71.1° 16:45	10.94	34%	43.5°
2045-11-15 Wed	51	—	unknown	18:40–21:30 (good, 2.83 h)	71.1° 16:45	10.97	43%	42.8°
2045-11-16 Thu	42	—	unknown	18:40–21:10 (good, 2.5 h)	71.1° 16:40	11.0	53%	44.7°
2045-11-17 Fri	35	—	unknown	18:40–19:50 (good, 1.17 h)	71.1° 16:35	11.03	62%	48.9°
2045-11-18 Sat	31	—	unknown	18:35–19:00 (good, 0.42 h)	71.1° 16:30	11.05	71%	54.9°
2045-11-19 Sun	29	—	unknown	18:35–18:45 (good, 0.17 h)	71.1° 16:30	11.08	79%	62.2°
2045-11-20 Mon	28	—	unknown	18:35–18:50 (good, 0.25 h)	71.1° 16:25	11.1	86%	70.4°
2045-11-21 Tue	31	—	unknown	18:35–19:10 (good, 0.58 h)	71.1° 16:20	11.13	93%	79.4°
2045-11-22 Wed	35	—	unknown	18:35–19:50 (good, 1.25 h)	71.1° 16:15	11.15	97%	88.8°
2045-11-23 Thu	40	—	unknown	18:35–20:30 (good, 1.92 h)	71.1° 16:10	11.18	99%	98.5°
2045-11-24 Fri	47	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 16:10	11.2	100%	108.2°
2045-11-25 Sat	53	—	unknown	18:35–21:00 (good, 2.42 h)	71.1° 16:05	11.22	97%	117.5°
2045-11-26 Sun	55	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 16:00	11.24	93%	125.9°
2045-11-27 Mon	61	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 15:55	11.26	86%	132.6°
2045-11-28 Tue	61	—	unknown	18:35–21:00 (good, 2.42 h)	71.1° 15:50	11.28	77%	136.6°
2045-11-29 Wed	59	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 15:50	11.3	67%	137.1°
2045-11-30 Thu	58	—	unknown	18:35–20:50 (good, 2.25 h)	71.1° 15:45	11.32	56%	133.9°
2045-12-01 Fri	56	—	unknown	18:35–20:45 (good, 2.17 h)	71.1° 15:40	11.34	44%	127.8°
2045-12-02 Sat	54	—	unknown	18:35–20:45 (good, 2.17 h)	71.1° 15:35	11.35	33%	119.7°
2045-12-03 Sun	52	—	unknown	18:35–20:40 (good, 2.08 h)	71.1° 15:35	11.37	23%	110.5°
2045-12-04 Mon	51	—	unknown	18:35–20:35 (good, 2.0 h)	71.1° 15:30	11.39	14%	100.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2045-11-05&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.