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 V1057 Cyg: 04-24 (73), 04-22 (72), 04-23 (72), 04-25 (72), 04-21 (71) — by astronomy; check the weather when the night is within four days.

2034-03-27astronomy score per night — click a bar for that night2034-04-25

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-03-27 Mon	48	—	unknown	03:45–05:40 (good, 1.92 h)	87.3° 10:00	8.35	60%	114.3°
2034-03-28 Tue	48	—	unknown	03:45–05:35 (good, 1.83 h)	87.3° 09:55	8.3	70%	119.5°
2034-03-29 Wed	48	—	unknown	03:45–05:35 (good, 1.83 h)	87.3° 09:50	8.24	79%	123.0°
2034-03-30 Thu	48	—	unknown	03:40–05:35 (good, 1.92 h)	87.3° 09:45	8.19	86%	124.8°
2034-03-31 Fri	43	—	unknown	03:40–05:30 (good, 1.83 h)	87.3° 09:40	8.13	92%	124.7°
2034-04-01 Sat	43	—	unknown	03:35–05:30 (good, 1.92 h)	87.3° 09:40	8.08	97%	122.8°
2034-04-02 Sun	41	—	unknown	03:35–05:25 (good, 1.83 h)	87.3° 09:35	8.02	99%	119.3°
2034-04-03 Mon	40	—	unknown	03:35–05:25 (good, 1.83 h)	87.3° 09:30	7.97	100%	114.7°
2034-04-04 Tue	38	—	unknown	03:35–05:25 (good, 1.83 h)	87.3° 09:25	7.91	99%	109.1°
2034-04-05 Wed	35	—	unknown	03:35–05:20 (good, 1.75 h)	87.3° 09:25	7.86	96%	102.9°
2034-04-06 Thu	34	—	unknown	03:35–05:20 (good, 1.75 h)	87.3° 09:20	7.8	91%	96.3°
2034-04-07 Fri	34	—	unknown	03:30–05:20 (good, 1.83 h)	87.3° 09:15	7.75	85%	89.6°
2034-04-08 Sat	33	—	unknown	03:25–05:15 (good, 1.83 h)	87.3° 09:10	7.69	78%	82.8°
2034-04-09 Sun	35	—	unknown	03:20–05:15 (good, 1.92 h)	87.3° 09:05	7.63	70%	76.1°
2034-04-10 Mon	37	—	unknown	03:10–05:10 (good, 2.0 h)	87.3° 09:05	7.58	60%	69.9°
2034-04-11 Tue	42	—	unknown	03:00–05:10 (good, 2.17 h)	87.3° 09:00	7.52	50%	64.2°
2034-04-12 Wed	50	—	unknown	02:40–05:10 (good, 2.5 h)	87.3° 08:55	7.46	40%	59.5°
2034-04-13 Thu	55	—	unknown	02:35–05:05 (good, 2.5 h)	87.3° 08:50	7.4	30%	56.3°
2034-04-14 Fri	61	—	unknown	02:30–05:05 (good, 2.58 h)	87.3° 08:45	7.35	20%	55.0°
2034-04-15 Sat	64	—	unknown	02:30–05:00 (good, 2.5 h)	87.3° 08:45	7.29	12%	56.2°
2034-04-16 Sun	65	—	unknown	02:25–05:00 (good, 2.58 h)	87.3° 08:40	7.23	5%	59.7°
2034-04-17 Mon	67	—	unknown	02:20–05:00 (good, 2.67 h)	87.3° 08:35	7.17	1%	65.3°
2034-04-18 Tue	68	—	unknown	02:15–04:55 (good, 2.67 h)	87.3° 08:30	7.12	0%	72.5°
2034-04-19 Wed	68	—	unknown	02:15–04:55 (good, 2.67 h)	87.3° 08:30	7.06	2%	80.7°
2034-04-20 Thu	69	—	unknown	02:10–04:50 (good, 2.67 h)	87.3° 08:25	7.0	7%	89.3°
2034-04-21 Fri	71	—	unknown	02:05–04:50 (good, 2.75 h)	87.3° 08:20	6.94	14%	97.7°
2034-04-22 Sat	72	—	unknown	02:00–04:50 (good, 2.83 h)	87.3° 08:15	6.88	23%	105.6°
2034-04-23 Sun	72	—	unknown	01:55–04:45 (good, 2.83 h)	87.3° 08:10	6.83	33%	112.5°
2034-04-24 Mon	73	—	unknown	01:55–04:45 (good, 2.83 h)	87.3° 08:10	6.77	44%	118.2°
2034-04-25 Tue	72	—	unknown	01:55–04:40 (good, 2.75 h)	87.3° 08:05	6.71	55%	122.2°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-03-27&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.