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 Seven Sisters: 10-03 (100), 10-04 (100), 10-05 (100), 10-06 (100), 10-07 (100) — by astronomy; check the weather when the night is within four days.

2029-09-29astronomy score per night — click a bar for that night2029-10-28

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-09-29 Sat	62	—	unknown	00:50–03:10 (good, 2.33 h)	72.5° 04:35	9.1	59%	26.8°
2029-09-30 Sun	81	—	unknown	23:25–05:50 (good, 6.42 h)	72.5° 04:30	9.14	50%	39.1°
2029-10-01 Mon	89	—	unknown	23:20–05:50 (good, 6.5 h)	72.5° 04:25	9.19	39%	51.8°
2029-10-02 Tue	97	—	unknown	23:15–05:50 (good, 6.58 h)	72.5° 04:20	9.24	29%	64.9°
2029-10-03 Wed	100	—	unknown	23:10–05:50 (good, 6.67 h)	72.5° 04:15	9.29	20%	78.5°
2029-10-04 Thu	100	—	unknown	23:05–05:50 (good, 6.75 h)	72.5° 04:15	9.34	12%	92.5°
2029-10-05 Fri	100	—	unknown	23:05–05:55 (good, 6.83 h)	72.5° 04:10	9.38	5%	107.0°
2029-10-06 Sat	100	—	unknown	23:00–05:55 (good, 6.92 h)	72.5° 04:05	9.43	1%	121.9°
2029-10-07 Sun	100	—	unknown	22:55–05:55 (good, 7.0 h)	72.5° 04:00	9.48	0%	137.0°
2029-10-08 Mon	100	—	unknown	22:50–05:55 (good, 7.08 h)	72.5° 03:55	9.52	2%	152.2°
2029-10-09 Tue	100	—	unknown	22:50–06:00 (good, 7.17 h)	72.5° 03:55	9.57	7%	167.3°
2029-10-10 Wed	100	—	unknown	22:45–06:00 (good, 7.25 h)	72.5° 03:50	9.61	14%	177.2°
2029-10-11 Thu	100	—	unknown	22:40–06:00 (good, 7.33 h)	72.5° 03:45	9.66	23%	163.1°
2029-10-12 Fri	100	—	unknown	22:35–06:00 (good, 7.42 h)	72.5° 03:40	9.7	33%	149.0°
2029-10-13 Sat	100	—	unknown	22:35–06:00 (good, 7.42 h)	72.5° 03:40	9.75	44%	135.3°
2029-10-14 Sun	100	—	unknown	22:35–06:05 (good, 7.5 h)	72.5° 03:35	9.79	55%	122.0°
2029-10-15 Mon	100	—	unknown	22:35–06:05 (good, 7.5 h)	72.5° 03:30	9.83	65%	109.1°
2029-10-16 Tue	100	—	unknown	22:40–06:05 (good, 7.42 h)	72.5° 03:25	9.88	74%	96.5°
2029-10-17 Wed	100	—	unknown	23:10–06:05 (good, 6.92 h)	72.5° 03:20	9.92	82%	84.1°
2029-10-18 Thu	100	—	unknown	00:35–06:10 (good, 5.58 h)	72.5° 03:20	9.96	89%	71.9°
2029-10-19 Fri	97	—	unknown	03:15–06:10 (good, 2.92 h)	72.5° 03:15	10.0	94%	59.8°
2029-10-20 Sat	58	—	unknown	22:20–06:10 (marginal, 7.83 h)	72.5° 03:10	10.05	98%	47.9°
2029-10-21 Sun	36	—	unknown	01:35–06:10 (marginal, 4.58 h)	72.5° 03:05	10.09	100%	36.0°
2029-10-22 Mon	24	—	unknown	04:00–06:10 (marginal, 2.17 h)	72.5° 03:00	10.13	100%	24.2°
2029-10-23 Tue	22	—	unknown	04:40–06:15 (marginal, 1.58 h)	72.5° 03:00	10.17	98%	12.4°
2029-10-24 Wed	24	—	unknown	21:55–01:00 (marginal, 3.08 h)	72.5° 02:55	10.21	94%	1.8°
2029-10-25 Thu	33	—	unknown	21:35–06:15 (marginal, 8.67 h)	72.5° 02:50	10.25	89%	11.6°
2029-10-26 Fri	45	—	unknown	21:20–06:15 (marginal, 8.92 h)	72.5° 02:45	10.29	83%	23.5°
2029-10-27 Sat	68	—	unknown	21:35–21:50 (good, 0.25 h)	72.5° 02:45	10.32	75%	35.7°
2029-10-28 Sun	86	—	unknown	20:35–03:00 (good, 6.42 h)	72.5° 01:40	10.36	66%	48.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-09-29&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.