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: 10-21 (100), 10-22 (99), 10-24 (99), 10-23 (98), 10-25 (97) — by astronomy; check the weather when the night is within four days.

2030-10-21astronomy score per night — click a bar for that night2030-11-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2030-10-21 Mon	100	—	unknown	20:05–00:00 (good, 3.92 h)	87.1° 18:00	10.08	28%	116.2°
2030-10-22 Tue	99	—	unknown	20:05–23:55 (good, 3.83 h)	87.1° 17:55	10.12	19%	111.4°
2030-10-23 Wed	98	—	unknown	20:05–23:50 (good, 3.75 h)	87.1° 17:50	10.16	11%	105.5°
2030-10-24 Thu	99	—	unknown	20:00–23:45 (good, 3.75 h)	87.1° 17:45	10.2	5%	98.7°
2030-10-25 Fri	97	—	unknown	20:00–23:40 (good, 3.67 h)	87.1° 17:45	10.24	1%	91.3°
2030-10-26 Sat	96	—	unknown	20:00–23:40 (good, 3.67 h)	87.1° 17:40	10.28	0%	83.6°
2030-10-27 Sun	94	—	unknown	19:00–22:35 (good, 3.58 h)	87.1° 16:35	10.32	2%	76.1°
2030-10-28 Mon	93	—	unknown	18:55–22:30 (good, 3.58 h)	87.1° 16:30	10.35	6%	69.4°
2030-10-29 Tue	90	—	unknown	18:55–22:25 (good, 3.5 h)	87.1° 16:25	10.39	13%	63.9°
2030-10-30 Wed	81	—	unknown	18:55–22:20 (good, 3.42 h)	87.1° 16:25	10.43	22%	60.1°
2030-10-31 Thu	71	—	unknown	18:55–22:20 (good, 3.42 h)	87.1° 16:20	10.47	32%	58.4°
2030-11-01 Fri	60	—	unknown	18:50–22:00 (good, 3.17 h)	87.1° 16:15	10.5	44%	58.8°
2030-11-02 Sat	50	—	unknown	18:50–21:45 (good, 2.92 h)	87.1° 16:10	10.54	55%	61.2°
2030-11-03 Sun	43	—	unknown	18:50–21:05 (good, 2.25 h)	87.1° 16:05	10.57	65%	65.2°
2030-11-04 Mon	39	—	unknown	18:50–20:10 (good, 1.33 h)	87.1° 16:05	10.61	75%	70.4°
2030-11-05 Tue	37	—	unknown	18:50–19:55 (good, 1.08 h)	87.1° 16:00	10.64	83%	76.3°
2030-11-06 Wed	38	—	unknown	18:45–19:55 (good, 1.17 h)	87.1° 15:55	10.68	90%	82.6°
2030-11-07 Thu	40	—	unknown	18:45–20:15 (good, 1.5 h)	87.1° 15:50	10.71	95%	89.1°
2030-11-08 Fri	43	—	unknown	18:45–20:40 (good, 1.92 h)	87.1° 15:50	10.74	98%	95.6°
2030-11-09 Sat	47	—	unknown	18:45–21:10 (good, 2.42 h)	87.1° 15:45	10.78	100%	101.8°
2030-11-10 Sun	52	—	unknown	18:45–21:15 (good, 2.5 h)	87.1° 15:40	10.81	99%	107.5°
2030-11-11 Mon	55	—	unknown	18:45–21:15 (good, 2.5 h)	87.1° 15:35	10.84	97%	112.5°
2030-11-12 Tue	66	—	unknown	18:40–21:20 (good, 2.67 h)	87.1° 15:30	10.87	93%	116.7°
2030-11-13 Wed	67	—	unknown	18:40–21:20 (good, 2.67 h)	87.1° 15:30	10.9	88%	119.7°
2030-11-14 Thu	67	—	unknown	18:40–21:15 (good, 2.58 h)	87.1° 15:25	10.93	81%	121.5°
2030-11-15 Fri	67	—	unknown	18:40–21:20 (good, 2.67 h)	87.1° 15:20	10.96	73%	121.7°
2030-11-16 Sat	66	—	unknown	18:40–21:15 (good, 2.58 h)	87.1° 15:15	10.99	64%	120.4°
2030-11-17 Sun	65	—	unknown	18:40–21:10 (good, 2.5 h)	87.1° 15:10	11.02	54%	117.6°
2030-11-18 Mon	63	—	unknown	18:40–21:10 (good, 2.5 h)	87.1° 15:10	11.04	44%	113.4°
2030-11-19 Tue	62	—	unknown	18:35–21:05 (good, 2.5 h)	87.1° 15:05	11.07	34%	108.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2030-10-21&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.