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: 11-17 (100), 11-18 (100), 11-19 (100), 11-20 (100), 11-21 (100) — by astronomy; check the weather when the night is within four days.

2028-11-17astronomy score per night — click a bar for that night2028-12-16

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2028-11-17 Fri	100	—	unknown	19:15–05:30 (good, 10.25 h)	72.5° 00:20	11.03	2%	165.6°
2028-11-18 Sat	100	—	unknown	19:10–05:25 (good, 10.25 h)	72.5° 00:15	11.06	7%	151.7°
2028-11-19 Sun	100	—	unknown	19:05–05:20 (good, 10.25 h)	72.5° 00:10	11.08	14%	138.3°
2028-11-20 Mon	100	—	unknown	19:05–05:20 (good, 10.25 h)	72.5° 00:05	11.11	21%	125.3°
2028-11-21 Tue	100	—	unknown	19:00–05:15 (good, 10.25 h)	72.5° 00:05	11.13	30%	112.7°
2028-11-22 Wed	100	—	unknown	19:00–05:10 (good, 10.17 h)	72.5° 00:00	11.16	40%	100.4°
2028-11-23 Thu	100	—	unknown	19:05–05:05 (good, 10.0 h)	72.5° 23:55	11.18	49%	88.3°
2028-11-24 Fri	100	—	unknown	19:10–05:00 (good, 9.83 h)	72.5° 23:50	11.2	59%	76.4°
2028-11-25 Sat	100	—	unknown	20:20–05:00 (good, 8.67 h)	72.5° 23:50	11.22	68%	64.6°
2028-11-26 Sun	93	—	unknown	22:50–04:55 (good, 6.08 h)	72.5° 23:45	11.25	76%	52.8°
2028-11-27 Mon	84	—	unknown	03:45–04:50 (good, 1.08 h)	72.5° 23:40	11.27	84%	40.8°
2028-11-28 Tue	59	—	unknown	20:40–05:15 (marginal, 8.58 h)	72.5° 23:35	11.29	90%	28.8°
2028-11-29 Wed	35	—	unknown	00:20–04:50 (marginal, 4.5 h)	72.5° 23:30	11.3	95%	16.5°
2028-11-30 Thu	25	—	unknown	02:25–04:30 (marginal, 2.08 h)	72.5° 23:30	11.32	98%	4.0°
2028-12-01 Fri	24	—	unknown	18:35–20:30 (marginal, 1.92 h)	72.5° 23:25	11.34	100%	8.8°
2028-12-02 Sat	29	—	unknown	18:35–21:55 (marginal, 3.33 h)	72.5° 23:20	11.36	99%	21.8°
2028-12-03 Sun	44	—	unknown	18:35–00:25 (marginal, 5.83 h)	72.5° 23:15	11.37	96%	35.0°
2028-12-04 Mon	85	—	unknown	18:35–19:15 (good, 0.67 h)	72.5° 23:10	11.39	91%	48.5°
2028-12-05 Tue	94	—	unknown	18:35–00:20 (good, 5.75 h)	72.5° 23:10	11.4	84%	62.1°
2028-12-06 Wed	100	—	unknown	18:35–02:45 (good, 8.17 h)	72.5° 23:05	11.41	75%	75.9°
2028-12-07 Thu	100	—	unknown	18:35–03:50 (good, 9.25 h)	72.5° 23:00	11.43	65%	89.8°
2028-12-08 Fri	100	—	unknown	18:35–03:55 (good, 9.33 h)	72.5° 22:55	11.44	54%	103.8°
2028-12-09 Sat	100	—	unknown	18:35–04:00 (good, 9.42 h)	72.5° 22:55	11.45	42%	117.9°
2028-12-10 Sun	100	—	unknown	18:35–03:55 (good, 9.33 h)	72.5° 22:50	11.46	31%	132.1°
2028-12-11 Mon	100	—	unknown	18:35–03:55 (good, 9.33 h)	72.5° 22:45	11.47	21%	146.4°
2028-12-12 Tue	100	—	unknown	18:35–03:50 (good, 9.25 h)	72.5° 22:40	11.48	12%	160.6°
2028-12-13 Wed	100	—	unknown	18:35–03:50 (good, 9.25 h)	72.5° 22:35	11.48	6%	174.8°
2028-12-14 Thu	100	—	unknown	18:35–03:45 (good, 9.17 h)	72.5° 22:35	11.49	2%	171.1°
2028-12-15 Fri	100	—	unknown	18:35–03:40 (good, 9.08 h)	72.5° 22:30	11.49	0%	157.2°
2028-12-16 Sat	100	—	unknown	18:35–03:35 (good, 9.0 h)	72.5° 22:25	11.5	1%	143.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2028-11-17&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.