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: 08-14 (100), 08-15 (100), 08-16 (100), 08-17 (100), 08-18 (100) — by astronomy; check the weather when the night is within four days.

2033-08-08astronomy score per night — click a bar for that night2033-09-06

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2033-08-08 Mon	70	—	unknown	00:25–04:35 (good, 4.17 h)	87.3° 01:10	6.26	95%	63.9°
2033-08-09 Tue	61	—	unknown	03:35–04:40 (good, 1.08 h)	87.3° 01:05	6.32	99%	58.7°
2033-08-10 Wed	55	—	unknown	22:20–04:40 (marginal, 6.33 h)	87.3° 01:00	6.37	100%	55.3°
2033-08-11 Thu	58	—	unknown	22:15–22:30 (good, 0.25 h)	87.3° 01:00	6.43	98%	54.4°
2033-08-12 Fri	67	—	unknown	22:15–23:40 (good, 1.42 h)	87.3° 00:55	6.49	93%	56.1°
2033-08-13 Sat	74	—	unknown	22:10–01:30 (good, 3.33 h)	87.3° 00:50	6.54	86%	60.3°
2033-08-14 Sun	100	—	unknown	22:10–04:10 (good, 6.0 h)	87.3° 00:45	6.6	77%	66.3°
2033-08-15 Mon	100	—	unknown	22:10–04:50 (good, 6.67 h)	87.3° 00:45	6.66	66%	73.5°
2033-08-16 Tue	100	—	unknown	22:05–04:50 (good, 6.75 h)	87.3° 00:40	6.72	55%	81.3°
2033-08-17 Wed	100	—	unknown	22:05–04:50 (good, 6.75 h)	87.3° 00:35	6.78	44%	89.3°
2033-08-18 Thu	100	—	unknown	22:05–04:50 (good, 6.75 h)	87.3° 00:30	6.83	34%	97.2°
2033-08-19 Fri	100	—	unknown	22:00–04:55 (good, 6.92 h)	87.3° 00:25	6.89	24%	104.7°
2033-08-20 Sat	100	—	unknown	22:00–04:55 (good, 6.92 h)	87.3° 00:25	6.95	16%	111.4°
2033-08-21 Sun	100	—	unknown	21:55–04:55 (good, 7.0 h)	87.3° 00:20	7.0	9%	117.2°
2033-08-22 Mon	100	—	unknown	21:55–05:00 (good, 7.08 h)	87.3° 00:15	7.06	4%	121.7°
2033-08-23 Tue	100	—	unknown	21:55–05:00 (good, 7.08 h)	87.3° 00:10	7.12	1%	124.6°
2033-08-24 Wed	100	—	unknown	21:50–05:00 (good, 7.17 h)	87.3° 00:05	7.18	0%	125.7°
2033-08-25 Thu	100	—	unknown	21:50–05:05 (good, 7.25 h)	87.3° 00:05	7.23	1%	124.9°
2033-08-26 Fri	100	—	unknown	21:45–05:05 (good, 7.33 h)	87.3° 00:00	7.29	4%	122.4°
2033-08-27 Sat	100	—	unknown	21:45–05:05 (good, 7.33 h)	87.3° 23:55	7.35	8%	118.5°
2033-08-28 Sun	100	—	unknown	21:45–05:05 (good, 7.33 h)	87.3° 23:50	7.4	14%	113.5°
2033-08-29 Mon	100	—	unknown	21:40–05:10 (good, 7.5 h)	87.3° 23:50	7.46	21%	107.6°
2033-08-30 Tue	100	—	unknown	21:40–05:10 (good, 7.5 h)	87.3° 23:45	7.52	30%	101.2°
2033-08-31 Wed	100	—	unknown	21:35–05:10 (good, 7.58 h)	87.3° 23:40	7.57	39%	94.3°
2033-09-01 Thu	100	—	unknown	21:35–05:10 (good, 7.58 h)	87.3° 23:35	7.63	48%	87.2°
2033-09-02 Fri	100	—	unknown	21:35–05:15 (good, 7.67 h)	87.3° 23:30	7.68	58%	80.0°
2033-09-03 Sat	100	—	unknown	21:30–05:15 (good, 7.75 h)	87.3° 23:30	7.74	68%	73.0°
2033-09-04 Sun	98	—	unknown	21:30–05:15 (good, 7.75 h)	87.3° 23:25	7.79	78%	66.4°
2033-09-05 Mon	90	—	unknown	21:25–05:20 (good, 7.92 h)	87.3° 23:20	7.85	86%	60.7°
2033-09-06 Tue	82	—	unknown	04:40–05:20 (good, 0.67 h)	87.3° 23:15	7.9	93%	56.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2033-08-08&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.