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 (58), 11-22 (57), 11-23 (56), 11-24 (54) — by astronomy; check the weather when the night is within four days.

2041-11-20astronomy score per night — click a bar for that night2041-12-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2041-11-20 Wed	60	—	unknown	18:35–21:00 (good, 2.42 h)	87.1° 15:00	11.1	8%	84.0°
2041-11-21 Thu	58	—	unknown	18:35–20:55 (good, 2.33 h)	87.1° 14:55	11.13	3%	79.4°
2041-11-22 Fri	57	—	unknown	18:35–20:50 (good, 2.25 h)	87.1° 14:50	11.15	1%	75.1°
2041-11-23 Sat	56	—	unknown	18:35–20:45 (good, 2.17 h)	87.1° 14:50	11.18	0%	71.4°
2041-11-24 Sun	54	—	unknown	18:35–20:45 (good, 2.17 h)	87.1° 14:45	11.2	2%	68.6°
2041-11-25 Mon	52	—	unknown	18:35–20:40 (good, 2.08 h)	87.1° 14:40	11.22	6%	66.9°
2041-11-26 Tue	49	—	unknown	18:35–20:35 (good, 2.0 h)	87.1° 14:35	11.24	12%	66.6°
2041-11-27 Wed	44	—	unknown	18:35–20:30 (good, 1.92 h)	87.1° 14:30	11.26	20%	67.6°
2041-11-28 Thu	39	—	unknown	18:35–20:20 (good, 1.75 h)	87.1° 14:30	11.28	29%	70.0°
2041-11-29 Fri	34	—	unknown	18:35–20:10 (good, 1.58 h)	87.1° 14:25	11.3	40%	73.6°
2041-11-30 Sat	30	—	unknown	18:35–20:00 (good, 1.42 h)	87.1° 14:20	11.32	51%	78.2°
2041-12-01 Sun	27	—	unknown	18:35–19:50 (good, 1.25 h)	87.1° 14:15	11.34	62%	83.4°
2041-12-02 Mon	24	—	unknown	18:35–19:45 (good, 1.17 h)	87.1° 14:15	11.35	73%	89.0°
2041-12-03 Tue	23	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 14:10	11.37	83%	94.6°
2041-12-04 Wed	23	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 14:05	11.38	90%	100.0°
2041-12-05 Thu	23	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 14:00	11.4	96%	104.8°
2041-12-06 Fri	24	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 13:55	11.41	99%	108.7°
2041-12-07 Sat	24	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 13:55	11.42	100%	111.6°
2041-12-08 Sun	25	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 13:50	11.44	98%	113.2°
2041-12-09 Mon	25	—	unknown	18:35–19:30 (good, 0.92 h)	87.1° 13:45	11.45	94%	113.5°
2041-12-10 Tue	29	—	unknown	18:35–19:30 (good, 0.92 h)	87.1° 13:40	11.46	89%	112.5°
2041-12-11 Wed	29	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 13:35	11.47	82%	110.4°
2041-12-12 Thu	27	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 13:35	11.47	74%	107.5°
2041-12-13 Fri	26	—	unknown	18:35–19:30 (good, 0.92 h)	87.1° 13:30	11.48	65%	103.9°
2041-12-14 Sat	25	—	unknown	18:35–19:25 (good, 0.83 h)	87.1° 13:25	11.49	56%	99.7°
2041-12-15 Sun	23	—	unknown	18:35–19:20 (good, 0.75 h)	87.1° 13:20	11.49	47%	95.3°
2041-12-16 Mon	23	—	unknown	18:35–19:15 (good, 0.67 h)	87.1° 13:15	11.5	37%	90.6°
2041-12-17 Tue	22	—	unknown	18:35–19:15 (good, 0.67 h)	87.1° 13:15	11.5	28%	85.8°
2041-12-18 Wed	20	—	unknown	18:35–19:10 (good, 0.58 h)	87.1° 13:10	11.5	20%	81.1°
2041-12-19 Thu	19	—	unknown	18:35–19:05 (good, 0.5 h)	87.1° 13:05	11.51	13%	76.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2041-11-20&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.