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: 04-13 (100), 04-14 (100), 04-15 (100), 04-16 (100), 04-17 (100) — by astronomy; check the weather when the night is within four days.

2034-03-29astronomy score per night — click a bar for that night2034-04-27

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-03-29 Wed	98	—	unknown	01:45–05:35 (good, 3.83 h)	87.1° 07:30	8.24	79%	118.3°
2034-03-30 Thu	95	—	unknown	01:45–05:35 (good, 3.83 h)	87.1° 07:25	8.19	86%	113.7°
2034-03-31 Fri	80	—	unknown	01:50–05:30 (good, 3.67 h)	87.1° 07:20	8.13	92%	108.1°
2034-04-01 Sat	72	—	unknown	01:50–05:30 (good, 3.67 h)	87.1° 07:15	8.08	97%	101.9°
2034-04-02 Sun	64	—	unknown	02:15–05:25 (good, 3.17 h)	87.1° 07:15	8.02	99%	95.4°
2034-04-03 Mon	57	—	unknown	02:50–05:25 (good, 2.58 h)	87.1° 07:10	7.97	100%	88.8°
2034-04-04 Tue	52	—	unknown	03:15–05:25 (good, 2.17 h)	87.1° 07:05	7.91	99%	82.3°
2034-04-05 Wed	48	—	unknown	03:30–05:20 (good, 1.83 h)	87.1° 07:00	7.86	96%	76.1°
2034-04-06 Thu	48	—	unknown	03:35–05:20 (good, 1.75 h)	87.1° 06:55	7.8	91%	70.3°
2034-04-07 Fri	49	—	unknown	03:10–05:20 (good, 2.17 h)	87.1° 06:55	7.75	85%	65.2°
2034-04-08 Sat	52	—	unknown	02:00–05:15 (good, 3.25 h)	87.1° 06:50	7.69	78%	61.0°
2034-04-09 Sun	61	—	unknown	01:15–05:15 (good, 4.0 h)	87.1° 06:45	7.63	70%	58.1°
2034-04-10 Mon	80	—	unknown	00:45–05:10 (good, 4.42 h)	87.1° 06:40	7.58	60%	56.7°
2034-04-11 Tue	90	—	unknown	00:45–05:10 (good, 4.42 h)	87.1° 06:35	7.52	50%	56.9°
2034-04-12 Wed	96	—	unknown	00:40–05:10 (good, 4.5 h)	87.1° 06:35	7.46	40%	59.1°
2034-04-13 Thu	100	—	unknown	00:35–05:05 (good, 4.5 h)	87.1° 06:30	7.4	30%	63.0°
2034-04-14 Fri	100	—	unknown	00:30–05:05 (good, 4.58 h)	87.1° 06:25	7.35	20%	68.4°
2034-04-15 Sat	100	—	unknown	00:25–05:00 (good, 4.58 h)	87.1° 06:20	7.29	12%	75.2°
2034-04-16 Sun	100	—	unknown	00:25–05:00 (good, 4.58 h)	87.1° 06:20	7.23	5%	82.9°
2034-04-17 Mon	100	—	unknown	00:20–05:00 (good, 4.67 h)	87.1° 06:15	7.17	1%	91.1°
2034-04-18 Tue	100	—	unknown	00:15–04:55 (good, 4.67 h)	87.1° 06:10	7.12	0%	99.4°
2034-04-19 Wed	100	—	unknown	00:10–04:55 (good, 4.75 h)	87.1° 06:05	7.06	2%	107.2°
2034-04-20 Thu	100	—	unknown	00:10–04:50 (good, 4.67 h)	87.1° 06:00	7.0	7%	114.0°
2034-04-21 Fri	100	—	unknown	00:05–04:50 (good, 4.75 h)	87.1° 06:00	6.94	14%	119.2°
2034-04-22 Sat	100	—	unknown	00:00–04:50 (good, 4.83 h)	87.1° 05:55	6.88	23%	122.4°
2034-04-23 Sun	100	—	unknown	00:00–04:45 (good, 4.75 h)	87.1° 05:50	6.83	33%	123.4°
2034-04-24 Mon	100	—	unknown	23:55–04:45 (good, 4.83 h)	87.1° 05:45	6.77	44%	122.2°
2034-04-25 Tue	100	—	unknown	23:55–04:40 (good, 4.75 h)	87.1° 05:40	6.71	55%	119.2°
2034-04-26 Wed	100	—	unknown	23:55–04:40 (good, 4.75 h)	87.1° 05:40	6.65	65%	114.8°
2034-04-27 Thu	100	—	unknown	23:55–04:40 (good, 4.75 h)	87.1° 05:35	6.59	74%	109.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-03-29&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.