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: 10-31 (89), 11-01 (89), 10-30 (88), 11-02 (87), 11-03 (86) — by astronomy; check the weather when the night is within four days.

2045-10-25astronomy score per night — click a bar for that night2045-11-23

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2045-10-25 Wed	53	—	unknown	20:00–22:20 (good, 2.33 h)	87.1° 17:40	10.25	100%	94.1°
2045-10-26 Thu	59	—	unknown	20:00–22:55 (good, 2.92 h)	87.1° 17:40	10.29	99%	99.5°
2045-10-27 Fri	65	—	unknown	20:00–23:10 (good, 3.17 h)	87.1° 17:35	10.33	95%	104.6°
2045-10-28 Sat	72	—	unknown	19:55–23:10 (good, 3.25 h)	87.1° 17:30	10.37	90%	109.1°
2045-10-29 Sun	84	—	unknown	18:55–22:10 (good, 3.25 h)	87.1° 16:25	10.41	82%	112.6°
2045-10-30 Mon	88	—	unknown	18:55–22:15 (good, 3.33 h)	87.1° 16:20	10.44	73%	115.0°
2045-10-31 Tue	89	—	unknown	18:55–22:10 (good, 3.25 h)	87.1° 16:20	10.48	63%	115.8°
2045-11-01 Wed	89	—	unknown	18:50–22:15 (good, 3.42 h)	87.1° 16:15	10.52	52%	115.0°
2045-11-02 Thu	87	—	unknown	18:50–22:10 (good, 3.33 h)	87.1° 16:10	10.55	41%	112.6°
2045-11-03 Fri	86	—	unknown	18:50–22:05 (good, 3.25 h)	87.1° 16:05	10.59	30%	108.9°
2045-11-04 Sat	84	—	unknown	18:50–22:00 (good, 3.17 h)	87.1° 16:05	10.62	20%	103.9°
2045-11-05 Sun	82	—	unknown	18:50–22:00 (good, 3.17 h)	87.1° 16:00	10.66	11%	98.3°
2045-11-06 Mon	81	—	unknown	18:45–21:55 (good, 3.17 h)	87.1° 15:55	10.69	5%	92.2°
2045-11-07 Tue	79	—	unknown	18:45–21:50 (good, 3.08 h)	87.1° 15:50	10.72	1%	86.0°
2045-11-08 Wed	79	—	unknown	18:45–21:45 (good, 3.0 h)	87.1° 15:45	10.76	0%	80.1°
2045-11-09 Thu	77	—	unknown	18:45–21:40 (good, 2.92 h)	87.1° 15:45	10.79	1%	74.9°
2045-11-10 Fri	75	—	unknown	18:45–21:40 (good, 2.92 h)	87.1° 15:40	10.82	5%	70.4°
2045-11-11 Sat	74	—	unknown	18:40–21:35 (good, 2.92 h)	87.1° 15:35	10.85	10%	67.1°
2045-11-12 Sun	67	—	unknown	18:40–21:30 (good, 2.83 h)	87.1° 15:30	10.88	17%	65.0°
2045-11-13 Mon	61	—	unknown	18:40–21:25 (good, 2.75 h)	87.1° 15:25	10.91	25%	64.1°
2045-11-14 Tue	53	—	unknown	18:40–21:10 (good, 2.5 h)	87.1° 15:25	10.94	34%	64.5°
2045-11-15 Wed	47	—	unknown	18:40–21:00 (good, 2.33 h)	87.1° 15:20	10.97	43%	66.1°
2045-11-16 Thu	41	—	unknown	18:40–20:50 (good, 2.17 h)	87.1° 15:15	11.0	53%	68.7°
2045-11-17 Fri	36	—	unknown	18:40–20:40 (good, 2.0 h)	87.1° 15:10	11.03	62%	72.2°
2045-11-18 Sat	33	—	unknown	18:35–20:00 (good, 1.42 h)	87.1° 15:10	11.05	71%	76.5°
2045-11-19 Sun	31	—	unknown	18:35–19:40 (good, 1.08 h)	87.1° 15:05	11.08	79%	81.3°
2045-11-20 Mon	30	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 15:00	11.1	86%	86.6°
2045-11-21 Tue	30	—	unknown	18:35–19:40 (good, 1.08 h)	87.1° 14:55	11.13	93%	92.1°
2045-11-22 Wed	32	—	unknown	18:35–20:00 (good, 1.42 h)	87.1° 14:50	11.15	97%	97.6°
2045-11-23 Thu	34	—	unknown	18:35–20:20 (good, 1.75 h)	87.1° 14:50	11.18	99%	103.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2045-10-25&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.