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.

2035-10-03astronomy score per night — click a bar for that night2035-11-01

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-10-03 Wed	100	—	unknown	23:15–05:50 (good, 6.58 h)	72.5° 04:20	9.27	6%	157.7°
2035-10-04 Thu	100	—	unknown	23:10–05:50 (good, 6.67 h)	72.5° 04:15	9.31	12%	167.9°
2035-10-05 Fri	100	—	unknown	23:05–05:55 (good, 6.83 h)	72.5° 04:10	9.36	19%	169.7°
2035-10-06 Sat	100	—	unknown	23:00–05:55 (good, 6.92 h)	72.5° 04:05	9.41	27%	161.1°
2035-10-07 Sun	100	—	unknown	23:00–05:55 (good, 6.92 h)	72.5° 04:05	9.45	36%	150.1°
2035-10-08 Mon	100	—	unknown	22:55–05:55 (good, 7.0 h)	72.5° 04:00	9.5	45%	138.8°
2035-10-09 Tue	100	—	unknown	22:55–05:55 (good, 7.0 h)	72.5° 03:55	9.55	55%	127.2°
2035-10-10 Wed	100	—	unknown	22:55–06:00 (good, 7.08 h)	72.5° 03:50	9.59	64%	115.5°
2035-10-11 Thu	100	—	unknown	22:55–06:00 (good, 7.08 h)	72.5° 03:50	9.64	73%	103.6°
2035-10-12 Fri	100	—	unknown	23:00–06:00 (good, 7.0 h)	72.5° 03:45	9.68	81%	91.4°
2035-10-13 Sat	100	—	unknown	00:05–06:00 (good, 5.92 h)	72.5° 03:40	9.73	89%	78.9°
2035-10-14 Sun	100	—	unknown	01:50–06:05 (good, 4.25 h)	72.5° 03:35	9.77	94%	66.1°
2035-10-15 Mon	64	—	unknown	04:55–06:05 (good, 1.17 h)	72.5° 03:30	9.81	98%	52.9°
2035-10-16 Tue	40	—	unknown	22:45–06:05 (marginal, 7.33 h)	72.5° 03:30	9.86	100%	39.6°
2035-10-17 Wed	26	—	unknown	03:40–06:05 (marginal, 2.42 h)	72.5° 03:25	9.9	99%	26.2°
2035-10-18 Thu	24	—	unknown	22:25–01:30 (marginal, 3.08 h)	72.5° 03:20	9.94	96%	13.9°
2035-10-19 Fri	32	—	unknown	22:05–06:10 (marginal, 8.08 h)	72.5° 03:15	9.98	90%	10.0°
2035-10-20 Sat	45	—	unknown	21:45–06:10 (marginal, 8.42 h)	72.5° 03:10	10.03	82%	20.4°
2035-10-21 Sun	71	—	unknown	22:05–22:20 (good, 0.25 h)	72.5° 03:10	10.07	72%	33.8°
2035-10-22 Mon	86	—	unknown	22:00–05:25 (good, 7.42 h)	72.5° 03:05	10.11	61%	47.7°
2035-10-23 Tue	95	—	unknown	21:55–06:15 (good, 8.33 h)	72.5° 03:00	10.15	50%	61.5°
2035-10-24 Wed	100	—	unknown	21:50–06:15 (good, 8.42 h)	72.5° 02:55	10.19	38%	75.3°
2035-10-25 Thu	100	—	unknown	21:45–06:15 (good, 8.5 h)	72.5° 02:55	10.23	28%	89.0°
2035-10-26 Fri	100	—	unknown	21:45–06:15 (good, 8.5 h)	72.5° 02:50	10.27	19%	102.4°
2035-10-27 Sat	100	—	unknown	21:40–05:15 (good, 8.58 h)	72.5° 02:45	10.31	11%	115.7°
2035-10-28 Sun	100	—	unknown	20:35–05:20 (good, 8.75 h)	72.5° 01:40	10.35	5%	128.8°
2035-10-29 Mon	100	—	unknown	20:30–05:20 (good, 8.83 h)	72.5° 01:35	10.38	2%	141.5°
2035-10-30 Tue	100	—	unknown	20:25–05:20 (good, 8.92 h)	72.5° 01:35	10.42	0%	153.7°
2035-10-31 Wed	100	—	unknown	20:25–05:20 (good, 8.92 h)	72.5° 01:30	10.46	1%	164.9°
2035-11-01 Thu	100	—	unknown	20:20–05:20 (good, 9.0 h)	72.5° 01:25	10.49	3%	170.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-10-03&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.