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: 08-04 (100), 08-05 (100), 08-06 (100), 08-07 (100), 08-08 (100) — by astronomy; check the weather when the night is within four days.

2034-07-31astronomy score per night — click a bar for that night2034-08-29

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-07-31 Mon	54	—	unknown	22:35–04:25 (marginal, 5.83 h)	87.3° 01:45	5.8	99%	57.1°
2034-08-01 Tue	58	—	unknown	22:35–23:20 (good, 0.75 h)	87.3° 01:40	5.85	97%	55.8°
2034-08-02 Wed	67	—	unknown	22:35–00:25 (good, 1.83 h)	87.3° 01:35	5.91	92%	56.6°
2034-08-03 Thu	74	—	unknown	22:30–02:15 (good, 3.75 h)	87.3° 01:30	5.96	85%	59.6°
2034-08-04 Fri	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.3° 01:25	6.02	76%	64.4°
2034-08-05 Sat	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.3° 01:25	6.07	65%	70.6°
2034-08-06 Sun	100	—	unknown	22:25–04:35 (good, 6.17 h)	87.3° 01:20	6.13	54%	77.8°
2034-08-07 Mon	100	—	unknown	22:25–04:35 (good, 6.17 h)	87.3° 01:15	6.19	42%	85.6°
2034-08-08 Tue	100	—	unknown	22:20–04:35 (good, 6.25 h)	87.3° 01:10	6.24	31%	93.6°
2034-08-09 Wed	100	—	unknown	22:20–04:40 (good, 6.33 h)	87.3° 01:05	6.3	21%	101.4°
2034-08-10 Thu	100	—	unknown	22:20–04:40 (good, 6.33 h)	87.3° 01:05	6.36	13%	108.7°
2034-08-11 Fri	100	—	unknown	22:15–04:40 (good, 6.42 h)	87.3° 01:00	6.42	6%	115.1°
2034-08-12 Sat	100	—	unknown	22:15–04:45 (good, 6.5 h)	87.3° 00:55	6.47	2%	120.0°
2034-08-13 Sun	100	—	unknown	22:15–04:45 (good, 6.5 h)	87.3° 00:50	6.53	0%	123.1°
2034-08-14 Mon	100	—	unknown	22:10–04:45 (good, 6.58 h)	87.3° 00:50	6.59	1%	124.2°
2034-08-15 Tue	100	—	unknown	22:10–04:50 (good, 6.67 h)	87.3° 00:45	6.65	4%	123.3°
2034-08-16 Wed	100	—	unknown	22:05–04:50 (good, 6.75 h)	87.3° 00:40	6.7	8%	120.5°
2034-08-17 Thu	100	—	unknown	22:05–04:50 (good, 6.75 h)	87.3° 00:35	6.76	15%	116.3°
2034-08-18 Fri	100	—	unknown	22:05–04:50 (good, 6.75 h)	87.3° 00:30	6.82	22%	111.0°
2034-08-19 Sat	100	—	unknown	22:00–04:55 (good, 6.92 h)	87.3° 00:30	6.88	31%	105.1°
2034-08-20 Sun	100	—	unknown	22:00–04:55 (good, 6.92 h)	87.3° 00:25	6.93	40%	98.8°
2034-08-21 Mon	100	—	unknown	21:55–04:55 (good, 7.0 h)	87.3° 00:20	6.99	49%	92.2°
2034-08-22 Tue	100	—	unknown	21:55–05:00 (good, 7.08 h)	87.3° 00:15	7.05	58%	85.5°
2034-08-23 Wed	100	—	unknown	21:55–05:00 (good, 7.08 h)	87.3° 00:10	7.11	68%	78.9°
2034-08-24 Thu	100	—	unknown	21:50–05:00 (good, 7.17 h)	87.3° 00:10	7.16	77%	72.6°
2034-08-25 Fri	98	—	unknown	21:50–05:00 (good, 7.17 h)	87.3° 00:05	7.22	84%	66.7°
2034-08-26 Sat	91	—	unknown	21:45–05:05 (good, 7.33 h)	87.3° 00:00	7.28	91%	61.7°
2034-08-27 Sun	60	—	unknown	02:40–03:20 (good, 0.67 h)	87.3° 23:55	7.33	96%	58.0°
2034-08-28 Mon	57	—	unknown	21:45–05:05 (marginal, 7.33 h)	87.3° 23:55	7.39	99%	56.0°
2034-08-29 Tue	60	—	unknown	21:05–05:10 (marginal, 8.08 h)	87.3° 23:50	7.45	100%	56.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-07-31&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.