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: 07-30 (100), 07-31 (100), 08-01 (100), 08-02 (100), 08-03 (100) — by astronomy; check the weather when the night is within four days.

2029-07-27astronomy score per night — click a bar for that night2029-08-25

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-07-27 Fri	68	—	unknown	22:45–01:40 (good, 2.92 h)	87.1° 23:35	5.59	94%	67.5°
2029-07-28 Sat	75	—	unknown	22:40–02:45 (good, 4.08 h)	87.1° 23:30	5.65	88%	72.1°
2029-07-29 Sun	80	—	unknown	22:40–03:35 (good, 4.92 h)	87.1° 23:30	5.7	81%	77.4°
2029-07-30 Mon	100	—	unknown	22:40–04:25 (good, 5.75 h)	87.1° 23:25	5.75	73%	83.1°
2029-07-31 Tue	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:20	5.81	64%	88.9°
2029-08-01 Wed	100	—	unknown	22:35–04:25 (good, 5.83 h)	87.1° 23:15	5.86	55%	94.8°
2029-08-02 Thu	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.1° 23:10	5.92	46%	100.5°
2029-08-03 Fri	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.1° 23:10	5.97	36%	105.9°
2029-08-04 Sat	100	—	unknown	22:30–04:30 (good, 6.0 h)	87.1° 23:05	6.03	27%	110.8°
2029-08-05 Sun	100	—	unknown	22:25–04:30 (good, 6.08 h)	87.1° 23:00	6.09	19%	114.9°
2029-08-06 Mon	100	—	unknown	22:25–04:35 (good, 6.17 h)	87.1° 22:55	6.14	11%	117.9°
2029-08-07 Tue	100	—	unknown	22:25–04:35 (good, 6.17 h)	87.1° 22:55	6.2	6%	119.5°
2029-08-08 Wed	100	—	unknown	22:20–04:35 (good, 6.25 h)	87.1° 22:50	6.26	2%	119.4°
2029-08-09 Thu	100	—	unknown	22:20–04:40 (good, 6.33 h)	87.1° 22:45	6.31	0%	117.4°
2029-08-10 Fri	100	—	unknown	22:20–04:40 (good, 6.33 h)	87.1° 22:40	6.37	1%	113.7°
2029-08-11 Sat	100	—	unknown	22:15–04:35 (good, 6.33 h)	87.1° 22:35	6.43	5%	108.5°
2029-08-12 Sun	100	—	unknown	22:15–04:30 (good, 6.25 h)	87.1° 22:35	6.49	11%	102.3°
2029-08-13 Mon	100	—	unknown	22:10–04:30 (good, 6.33 h)	87.1° 22:30	6.54	19%	95.4°
2029-08-14 Tue	100	—	unknown	22:10–04:25 (good, 6.25 h)	87.1° 22:25	6.6	29%	88.3°
2029-08-15 Wed	100	—	unknown	22:10–04:20 (good, 6.17 h)	87.1° 22:20	6.66	40%	81.3°
2029-08-16 Thu	100	—	unknown	22:05–04:15 (good, 6.17 h)	87.1° 22:15	6.72	52%	74.8°
2029-08-17 Fri	100	—	unknown	22:05–04:10 (good, 6.08 h)	87.1° 22:15	6.77	63%	69.2°
2029-08-18 Sat	95	—	unknown	22:05–04:10 (good, 6.08 h)	87.1° 22:10	6.83	73%	64.7°
2029-08-19 Sun	87	—	unknown	22:00–04:05 (good, 6.08 h)	87.1° 22:05	6.89	82%	61.7°
2029-08-20 Mon	75	—	unknown	22:00–02:40 (good, 4.67 h)	87.1° 22:00	6.95	90%	60.4°
2029-08-21 Tue	58	—	unknown	21:55–22:05 (good, 0.17 h)	87.1° 21:55	7.0	95%	60.8°
2029-08-22 Wed	55	—	unknown	21:55–22:05 (good, 0.17 h)	87.1° 21:55	7.06	98%	62.8°
2029-08-23 Thu	56	—	unknown	21:55–22:40 (good, 0.75 h)	87.1° 21:50	7.12	100%	66.2°
2029-08-24 Fri	61	—	unknown	21:50–23:40 (good, 1.83 h)	87.1° 21:45	7.17	99%	70.6°
2029-08-25 Sat	69	—	unknown	21:50–00:45 (good, 2.92 h)	87.1° 21:40	7.23	96%	75.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-07-27&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.