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: 07-10 (100), 07-11 (100), 07-12 (100), 07-13 (100), 07-14 (100) — by astronomy; check the weather when the night is within four days.

2034-07-10astronomy score per night — click a bar for that night2034-08-08

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-07-10 Mon	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:45	4.8	29%	106.1°
2034-07-11 Tue	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:40	4.84	19%	112.7°
2034-07-12 Wed	100	—	unknown	23:05–03:55 (good, 4.83 h)	87.1° 00:35	4.88	11%	118.1°
2034-07-13 Thu	100	—	unknown	23:00–03:55 (good, 4.92 h)	87.1° 00:30	4.92	5%	121.7°
2034-07-14 Fri	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:30	4.96	1%	123.1°
2034-07-15 Sat	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:25	5.0	0%	122.1°
2034-07-16 Sun	100	—	unknown	23:00–04:00 (good, 5.0 h)	87.1° 00:20	5.04	2%	119.1°
2034-07-17 Mon	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:15	5.09	6%	114.4°
2034-07-18 Tue	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:10	5.13	12%	108.7°
2034-07-19 Wed	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:10	5.18	19%	102.4°
2034-07-20 Thu	100	—	unknown	22:55–04:05 (good, 5.17 h)	87.1° 00:05	5.23	28%	95.7°
2034-07-21 Fri	100	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 00:00	5.28	37%	89.1°
2034-07-22 Sat	100	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 23:55	5.33	47%	82.5°
2034-07-23 Sun	100	—	unknown	22:50–04:10 (good, 5.33 h)	87.1° 23:50	5.38	56%	76.3°
2034-07-24 Mon	100	—	unknown	22:50–04:15 (good, 5.42 h)	87.1° 23:50	5.43	65%	70.6°
2034-07-25 Tue	100	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 23:45	5.48	74%	65.5°
2034-07-26 Wed	96	—	unknown	22:45–04:15 (good, 5.5 h)	87.1° 23:40	5.53	82%	61.3°
2034-07-27 Thu	90	—	unknown	22:45–04:20 (good, 5.58 h)	87.1° 23:35	5.58	89%	58.4°
2034-07-28 Fri	62	—	unknown	01:30–04:20 (good, 2.83 h)	87.1° 23:35	5.63	94%	57.0°
2034-07-29 Sat	53	—	unknown	22:40–04:20 (marginal, 5.67 h)	87.1° 23:30	5.69	98%	57.3°
2034-07-30 Sun	53	—	unknown	22:40–04:20 (marginal, 5.67 h)	87.1° 23:25	5.74	100%	59.4°
2034-07-31 Mon	59	—	unknown	22:35–23:35 (good, 1.0 h)	87.1° 23:20	5.8	99%	63.3°
2034-08-01 Tue	69	—	unknown	22:35–01:30 (good, 2.92 h)	87.1° 23:15	5.85	97%	68.6°
2034-08-02 Wed	75	—	unknown	22:35–02:40 (good, 4.08 h)	87.1° 23:15	5.91	92%	75.0°
2034-08-03 Thu	82	—	unknown	22:30–03:35 (good, 5.08 h)	87.1° 23:10	5.96	85%	82.1°
2034-08-04 Fri	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.1° 23:05	6.02	76%	89.7°
2034-08-05 Sat	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.1° 23:00	6.07	65%	97.3°
2034-08-06 Sun	100	—	unknown	22:25–04:35 (good, 6.17 h)	87.1° 22:55	6.13	54%	104.7°
2034-08-07 Mon	100	—	unknown	22:25–04:35 (good, 6.17 h)	87.1° 22:55	6.19	42%	111.4°
2034-08-08 Tue	100	—	unknown	22:20–04:35 (good, 6.25 h)	87.1° 22:50	6.24	31%	117.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-07-10&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.