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: 11-20 (60), 11-21 (59), 11-19 (58), 11-22 (57), 11-23 (56) — by astronomy; check the weather when the night is within four days.

2043-11-15astronomy score per night — click a bar for that night2043-12-14

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2043-11-15 Sun	39	—	unknown	18:40–20:30 (good, 1.83 h)	87.1° 15:20	10.96	98%	98.1°
2043-11-16 Mon	42	—	unknown	18:40–20:50 (good, 2.17 h)	87.1° 15:15	10.98	100%	103.5°
2043-11-17 Tue	46	—	unknown	18:40–20:50 (good, 2.17 h)	87.1° 15:15	11.01	98%	108.1°
2043-11-18 Wed	49	—	unknown	18:40–20:55 (good, 2.25 h)	87.1° 15:10	11.04	94%	111.4°
2043-11-19 Thu	58	—	unknown	18:35–20:55 (good, 2.33 h)	87.1° 15:05	11.07	87%	113.2°
2043-11-20 Fri	60	—	unknown	18:35–20:50 (good, 2.25 h)	87.1° 15:00	11.09	78%	113.4°
2043-11-21 Sat	59	—	unknown	18:35–20:55 (good, 2.33 h)	87.1° 15:00	11.12	68%	112.0°
2043-11-22 Sun	57	—	unknown	18:35–20:55 (good, 2.33 h)	87.1° 14:55	11.14	57%	109.4°
2043-11-23 Mon	56	—	unknown	18:35–20:50 (good, 2.25 h)	87.1° 14:50	11.16	46%	105.8°
2043-11-24 Tue	55	—	unknown	18:35–20:45 (good, 2.17 h)	87.1° 14:45	11.19	36%	101.6°
2043-11-25 Wed	53	—	unknown	18:35–20:40 (good, 2.08 h)	87.1° 14:40	11.21	27%	97.0°
2043-11-26 Thu	52	—	unknown	18:35–20:35 (good, 2.0 h)	87.1° 14:40	11.23	19%	92.2°
2043-11-27 Fri	50	—	unknown	18:35–20:35 (good, 2.0 h)	87.1° 14:35	11.25	12%	87.4°
2043-11-28 Sat	48	—	unknown	18:35–20:30 (good, 1.92 h)	87.1° 14:30	11.27	6%	82.7°
2043-11-29 Sun	46	—	unknown	18:35–20:25 (good, 1.83 h)	87.1° 14:25	11.29	3%	78.3°
2043-11-30 Mon	45	—	unknown	18:35–20:20 (good, 1.75 h)	87.1° 14:20	11.31	1%	74.4°
2043-12-01 Tue	44	—	unknown	18:35–20:20 (good, 1.75 h)	87.1° 14:20	11.33	0%	71.1°
2043-12-02 Wed	42	—	unknown	18:35–20:15 (good, 1.67 h)	87.1° 14:15	11.35	2%	68.6°
2043-12-03 Thu	40	—	unknown	18:35–20:10 (good, 1.58 h)	87.1° 14:10	11.36	5%	67.0°
2043-12-04 Fri	39	—	unknown	18:35–20:05 (good, 1.5 h)	87.1° 14:05	11.38	10%	66.4°
2043-12-05 Sat	34	—	unknown	18:35–20:00 (good, 1.42 h)	87.1° 14:05	11.39	16%	66.9°
2043-12-06 Sun	31	—	unknown	18:35–19:50 (good, 1.25 h)	87.1° 14:00	11.41	24%	68.5°
2043-12-07 Mon	27	—	unknown	18:35–19:40 (good, 1.08 h)	87.1° 13:55	11.42	33%	71.2°
2043-12-08 Tue	23	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 13:50	11.43	42%	74.8°
2043-12-09 Wed	21	—	unknown	18:35–19:25 (good, 0.83 h)	87.1° 13:45	11.44	53%	79.2°
2043-12-10 Thu	18	—	unknown	18:35–19:15 (good, 0.67 h)	87.1° 13:45	11.45	64%	84.2°
2043-12-11 Fri	16	—	unknown	18:35–19:05 (good, 0.5 h)	87.1° 13:40	11.46	74%	89.7°
2043-12-12 Sat	16	—	unknown	18:35–19:00 (good, 0.42 h)	87.1° 13:35	11.47	83%	95.4°
2043-12-13 Sun	16	—	unknown	18:35–19:00 (good, 0.42 h)	87.1° 13:30	11.48	91%	101.0°
2043-12-14 Mon	16	—	unknown	18:35–19:00 (good, 0.42 h)	87.1° 13:25	11.49	97%	106.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2043-11-15&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.