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 HD 189733: 04-12 (56), 04-14 (55), 04-09 (54), 04-10 (54), 04-11 (54) — by astronomy; check the weather when the night is within four days.

2030-03-24astronomy score per night — click a bar for that night2030-04-22

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2030-03-24 Sun	22	—	unknown	03:40–04:45 (good, 1.08 h)	71.1° 08:10	8.51	66%	64.2°
2030-03-25 Mon	24	—	unknown	03:30–04:45 (good, 1.25 h)	71.1° 08:10	8.46	55%	54.5°
2030-03-26 Tue	27	—	unknown	03:20–04:40 (good, 1.33 h)	71.1° 08:05	8.41	44%	46.3°
2030-03-27 Wed	32	—	unknown	03:00–04:40 (good, 1.67 h)	71.1° 08:00	8.35	34%	40.6°
2030-03-28 Thu	37	—	unknown	02:55–04:35 (good, 1.67 h)	71.1° 07:55	8.3	24%	38.3°
2030-03-29 Fri	42	—	unknown	02:50–04:35 (good, 1.75 h)	71.1° 07:50	8.24	16%	39.7°
2030-03-30 Sat	45	—	unknown	02:45–05:35 (good, 1.83 h)	71.1° 08:50	8.19	9%	44.4°
2030-03-31 Sun	45	—	unknown	03:45–05:30 (good, 1.75 h)	71.1° 08:45	8.14	4%	51.2°
2030-04-01 Mon	47	—	unknown	03:40–05:30 (good, 1.83 h)	71.1° 08:40	8.08	1%	59.4°
2030-04-02 Tue	46	—	unknown	03:35–05:25 (good, 1.83 h)	71.1° 08:35	8.03	0%	68.3°
2030-04-03 Wed	48	—	unknown	03:30–05:25 (good, 1.92 h)	71.1° 08:35	7.97	1%	77.5°
2030-04-04 Thu	50	—	unknown	03:30–05:25 (good, 1.92 h)	71.1° 08:30	7.91	4%	86.9°
2030-04-05 Fri	50	—	unknown	03:25–05:20 (good, 1.92 h)	71.1° 08:25	7.86	8%	96.2°
2030-04-06 Sat	51	—	unknown	03:20–05:20 (good, 2.0 h)	71.1° 08:20	7.8	14%	105.4°
2030-04-07 Sun	52	—	unknown	03:15–05:20 (good, 2.08 h)	71.1° 08:15	7.75	21%	114.3°
2030-04-08 Mon	52	—	unknown	03:10–05:15 (good, 2.08 h)	71.1° 08:15	7.69	29%	122.7°
2030-04-09 Tue	54	—	unknown	03:10–05:15 (good, 2.08 h)	71.1° 08:10	7.63	38%	130.4°
2030-04-10 Wed	54	—	unknown	03:05–05:10 (good, 2.08 h)	71.1° 08:05	7.58	48%	136.7°
2030-04-11 Thu	54	—	unknown	03:05–05:10 (good, 2.08 h)	71.1° 08:00	7.52	58%	140.8°
2030-04-12 Fri	56	—	unknown	03:00–05:10 (good, 2.17 h)	71.1° 07:55	7.46	68%	141.8°
2030-04-13 Sat	54	—	unknown	03:00–05:05 (good, 2.08 h)	71.1° 07:55	7.41	77%	139.1°
2030-04-14 Sun	55	—	unknown	02:55–05:05 (good, 2.17 h)	71.1° 07:50	7.35	86%	133.0°
2030-04-15 Mon	50	—	unknown	02:55–05:00 (good, 2.08 h)	71.1° 07:45	7.29	93%	124.4°
2030-04-16 Tue	46	—	unknown	02:55–05:00 (good, 2.08 h)	71.1° 07:40	7.23	98%	114.2°
2030-04-17 Wed	41	—	unknown	03:00–05:00 (good, 2.0 h)	71.1° 07:40	7.18	100%	102.9°
2030-04-18 Thu	35	—	unknown	03:10–04:55 (good, 1.75 h)	71.1° 07:35	7.12	99%	91.1°
2030-04-19 Fri	31	—	unknown	03:50–04:55 (good, 1.08 h)	71.1° 07:30	7.06	95%	79.2°
2030-04-20 Sat	28	—	unknown	04:15–04:50 (good, 0.58 h)	71.1° 07:25	7.0	89%	67.8°
2030-04-21 Sun	28	—	unknown	04:15–04:50 (good, 0.58 h)	71.1° 07:20	6.94	80%	57.2°
2030-04-22 Mon	31	—	unknown	03:35–04:50 (good, 1.25 h)	71.1° 07:20	6.89	70%	48.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2030-03-24&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.