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: 10-18 (100), 10-19 (100), 10-20 (100), 10-21 (100), 10-22 (100) — by astronomy; check the weather when the night is within four days.

2044-10-18astronomy score per night — click a bar for that night2044-11-16

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2044-10-18 Tue	100	—	unknown	22:10–06:10 (good, 8.0 h)	72.5° 03:20	9.98	5%	121.0°
2044-10-19 Wed	100	—	unknown	22:10–06:10 (good, 8.0 h)	72.6° 03:15	10.02	1%	134.5°
2044-10-20 Thu	100	—	unknown	22:05–06:10 (good, 8.08 h)	72.6° 03:10	10.06	0%	147.7°
2044-10-21 Fri	100	—	unknown	22:00–06:10 (good, 8.17 h)	72.6° 03:05	10.1	1%	160.7°
2044-10-22 Sat	100	—	unknown	21:55–06:10 (good, 8.25 h)	72.6° 03:00	10.14	4%	173.3°
2044-10-23 Sun	100	—	unknown	21:50–06:15 (good, 8.42 h)	72.6° 03:00	10.18	9%	174.1°
2044-10-24 Mon	100	—	unknown	21:50–06:15 (good, 8.42 h)	72.6° 02:55	10.22	15%	161.9°
2044-10-25 Tue	100	—	unknown	21:45–06:15 (good, 8.5 h)	72.6° 02:50	10.26	23%	149.9°
2044-10-26 Wed	100	—	unknown	21:40–06:15 (good, 8.58 h)	72.6° 02:45	10.3	31%	138.1°
2044-10-27 Thu	100	—	unknown	21:40–06:20 (good, 8.67 h)	72.6° 02:40	10.34	40%	126.2°
2044-10-28 Fri	100	—	unknown	21:40–06:20 (good, 8.67 h)	72.6° 02:40	10.38	49%	114.4°
2044-10-29 Sat	100	—	unknown	21:40–05:20 (good, 8.67 h)	72.6° 02:35	10.41	59%	102.4°
2044-10-30 Sun	100	—	unknown	20:45–05:20 (good, 8.58 h)	72.6° 01:30	10.45	68%	90.3°
2044-10-31 Mon	100	—	unknown	21:20–05:20 (good, 8.0 h)	72.6° 01:25	10.49	77%	77.9°
2044-11-01 Tue	100	—	unknown	23:05–05:25 (good, 6.33 h)	72.5° 01:25	10.52	85%	65.1°
2044-11-02 Wed	92	—	unknown	02:25–05:25 (good, 3.0 h)	72.6° 01:20	10.56	92%	51.9°
2044-11-03 Thu	53	—	unknown	21:05–05:25 (marginal, 8.33 h)	72.6° 01:15	10.6	97%	38.4°
2044-11-04 Fri	31	—	unknown	02:05–05:25 (marginal, 3.33 h)	72.6° 01:10	10.63	99%	24.5°
2044-11-05 Sat	24	—	unknown	03:30–05:25 (marginal, 1.92 h)	72.6° 01:05	10.66	100%	10.3°
2044-11-06 Sun	24	—	unknown	20:10–22:10 (marginal, 2.0 h)	72.6° 01:05	10.7	97%	4.3°
2044-11-07 Mon	34	—	unknown	19:45–00:40 (marginal, 4.92 h)	72.6° 01:00	10.73	92%	18.8°
2044-11-08 Tue	50	—	unknown	19:30–05:30 (marginal, 10.0 h)	72.6° 00:55	10.76	84%	33.4°
2044-11-09 Wed	83	—	unknown	19:45–00:10 (good, 4.42 h)	72.6° 00:50	10.8	75%	48.0°
2044-11-10 Thu	93	—	unknown	19:40–03:55 (good, 8.25 h)	72.6° 00:45	10.83	65%	62.3°
2044-11-11 Fri	100	—	unknown	19:35–05:30 (good, 9.92 h)	72.6° 00:45	10.86	53%	76.5°
2044-11-12 Sat	100	—	unknown	19:35–05:35 (good, 10.0 h)	72.6° 00:40	10.89	42%	90.4°
2044-11-13 Sun	100	—	unknown	19:30–05:35 (good, 10.08 h)	72.6° 00:35	10.92	32%	104.1°
2044-11-14 Mon	100	—	unknown	19:25–05:35 (good, 10.17 h)	72.6° 00:30	10.95	22%	117.6°
2044-11-15 Tue	100	—	unknown	19:20–05:35 (good, 10.25 h)	72.5° 00:30	10.98	14%	130.8°
2044-11-16 Wed	100	—	unknown	19:20–05:35 (good, 10.25 h)	72.6° 00:25	11.01	8%	143.9°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2044-10-18&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.