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: 03-10 (89), 03-11 (89), 03-12 (89), 03-13 (89), 03-14 (89) — by astronomy; check the weather when the night is within four days.

2030-02-22astronomy score per night — click a bar for that night2030-03-23

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2030-02-22 Fri	41	—	unknown	03:20–05:35 (good, 2.25 h)	87.1° 08:45	9.95	74%	83.6°
2030-02-23 Sat	44	—	unknown	03:10–05:35 (good, 2.42 h)	87.1° 08:40	9.91	63%	76.7°
2030-02-24 Sun	48	—	unknown	03:00–05:30 (good, 2.5 h)	87.1° 08:40	9.87	52%	70.5°
2030-02-25 Mon	55	—	unknown	02:40–05:30 (good, 2.83 h)	87.1° 08:35	9.82	40%	65.4°
2030-02-26 Tue	62	—	unknown	02:35–05:30 (good, 2.92 h)	87.1° 08:30	9.78	30%	61.7°
2030-02-27 Wed	69	—	unknown	02:30–05:30 (good, 3.0 h)	87.1° 08:25	9.74	20%	59.7°
2030-02-28 Thu	74	—	unknown	02:30–05:25 (good, 2.92 h)	87.1° 08:25	9.69	12%	59.7°
2030-03-01 Fri	77	—	unknown	02:25–05:25 (good, 3.0 h)	87.1° 08:20	9.65	6%	61.4°
2030-03-02 Sat	79	—	unknown	02:20–05:25 (good, 3.08 h)	87.1° 08:15	9.6	2%	64.8°
2030-03-03 Sun	79	—	unknown	02:15–05:20 (good, 3.08 h)	87.1° 08:10	9.55	0%	69.4°
2030-03-04 Mon	81	—	unknown	02:15–05:20 (good, 3.08 h)	87.1° 08:05	9.51	1%	74.8°
2030-03-05 Tue	83	—	unknown	02:10–05:20 (good, 3.17 h)	87.1° 08:05	9.46	3%	80.7°
2030-03-06 Wed	83	—	unknown	02:05–05:15 (good, 3.17 h)	87.1° 08:00	9.41	7%	86.9°
2030-03-07 Thu	84	—	unknown	02:00–05:15 (good, 3.25 h)	87.1° 07:55	9.37	13%	93.1°
2030-03-08 Fri	86	—	unknown	01:55–05:15 (good, 3.33 h)	87.1° 07:50	9.32	20%	99.0°
2030-03-09 Sat	87	—	unknown	01:55–05:10 (good, 3.25 h)	87.1° 07:45	9.27	28%	104.7°
2030-03-10 Sun	89	—	unknown	01:50–05:10 (good, 3.33 h)	87.1° 07:45	9.22	37%	109.8°
2030-03-11 Mon	89	—	unknown	01:45–05:10 (good, 3.42 h)	87.1° 07:40	9.17	46%	114.2°
2030-03-12 Tue	89	—	unknown	01:45–05:05 (good, 3.33 h)	87.1° 07:35	9.12	56%	117.7°
2030-03-13 Wed	89	—	unknown	01:45–05:05 (good, 3.33 h)	87.1° 07:30	9.07	65%	119.9°
2030-03-14 Thu	89	—	unknown	01:40–05:05 (good, 3.42 h)	87.1° 07:30	9.02	74%	120.7°
2030-03-15 Fri	87	—	unknown	01:40–05:00 (good, 3.33 h)	87.1° 07:25	8.97	83%	119.8°
2030-03-16 Sat	85	—	unknown	01:40–05:00 (good, 3.33 h)	87.1° 07:20	8.92	90%	117.2°
2030-03-17 Sun	74	—	unknown	01:40–05:00 (good, 3.33 h)	87.1° 07:15	8.87	96%	112.9°
2030-03-18 Mon	67	—	unknown	01:40–04:55 (good, 3.25 h)	87.1° 07:10	8.82	99%	107.3°
2030-03-19 Tue	61	—	unknown	01:45–04:55 (good, 3.17 h)	87.1° 07:10	8.77	100%	100.6°
2030-03-20 Wed	56	—	unknown	02:00–04:50 (good, 2.83 h)	87.1° 07:05	8.72	98%	93.3°
2030-03-21 Thu	52	—	unknown	02:10–04:50 (good, 2.67 h)	87.1° 07:00	8.67	93%	85.8°
2030-03-22 Fri	52	—	unknown	02:00–04:50 (good, 2.83 h)	87.1° 06:55	8.62	86%	78.5°
2030-03-23 Sat	53	—	unknown	01:25–04:45 (good, 3.33 h)	87.1° 06:50	8.56	77%	71.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2030-02-22&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.