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: 11-27 (100), 11-28 (100), 11-29 (100), 11-30 (100), 12-01 (100) — by astronomy; check the weather when the night is within four days.

2046-11-27astronomy score per night — click a bar for that night2046-12-26

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-11-27 Tue	100	—	unknown	18:35–04:55 (good, 10.33 h)	72.6° 23:40	11.26	0%	173.8°
2046-11-28 Wed	100	—	unknown	18:35–04:50 (good, 10.25 h)	72.6° 23:40	11.28	1%	159.4°
2046-11-29 Thu	100	—	unknown	18:35–04:45 (good, 10.17 h)	72.6° 23:35	11.3	5%	145.4°
2046-11-30 Fri	100	—	unknown	18:35–04:40 (good, 10.08 h)	72.6° 23:30	11.32	11%	131.7°
2046-12-01 Sat	100	—	unknown	18:35–04:40 (good, 10.08 h)	72.6° 23:25	11.33	19%	118.5°
2046-12-02 Sun	100	—	unknown	18:35–04:35 (good, 10.0 h)	72.6° 23:25	11.35	27%	105.7°
2046-12-03 Mon	100	—	unknown	18:35–04:30 (good, 9.92 h)	72.6° 23:20	11.37	36%	93.3°
2046-12-04 Tue	100	—	unknown	18:35–04:25 (good, 9.83 h)	72.6° 23:15	11.38	46%	81.1°
2046-12-05 Wed	100	—	unknown	18:35–04:20 (good, 9.75 h)	72.6° 23:10	11.4	56%	69.1°
2046-12-06 Thu	96	—	unknown	20:05–04:20 (good, 8.25 h)	72.6° 23:05	11.41	65%	57.3°
2046-12-07 Fri	88	—	unknown	23:20–04:15 (good, 4.92 h)	72.6° 23:05	11.42	74%	45.5°
2046-12-08 Sat	80	—	unknown	03:40–04:10 (good, 0.5 h)	72.6° 23:00	11.43	81%	33.6°
2046-12-09 Sun	45	—	unknown	18:35–04:25 (marginal, 9.83 h)	72.6° 22:55	11.44	88%	21.6°
2046-12-10 Mon	31	—	unknown	23:55–04:05 (marginal, 4.17 h)	72.6° 22:50	11.45	94%	9.4°
2046-12-11 Tue	22	—	unknown	18:35–19:35 (marginal, 1.0 h)	72.6° 22:45	11.46	98%	2.9°
2046-12-12 Wed	23	—	unknown	18:35–20:35 (marginal, 2.0 h)	72.6° 22:45	11.47	100%	15.6°
2046-12-13 Thu	28	—	unknown	18:35–21:35 (marginal, 3.0 h)	72.6° 22:40	11.48	100%	28.4°
2046-12-14 Fri	49	—	unknown	18:35–01:20 (marginal, 6.75 h)	72.6° 22:35	11.49	98%	41.5°
2046-12-15 Sat	88	—	unknown	18:35–21:10 (good, 2.58 h)	72.6° 22:30	11.49	93%	54.8°
2046-12-16 Sun	97	—	unknown	18:35–00:35 (good, 6.0 h)	72.6° 22:30	11.5	87%	68.3°
2046-12-17 Mon	100	—	unknown	18:35–02:20 (good, 7.75 h)	72.6° 22:25	11.5	78%	81.9°
2046-12-18 Tue	100	—	unknown	18:35–03:10 (good, 8.58 h)	72.6° 22:20	11.5	69%	95.7°
2046-12-19 Wed	100	—	unknown	18:35–03:15 (good, 8.67 h)	72.6° 22:15	11.51	58%	109.7°
2046-12-20 Thu	100	—	unknown	18:35–03:20 (good, 8.75 h)	72.6° 22:10	11.51	46%	123.8°
2046-12-21 Fri	100	—	unknown	18:35–03:15 (good, 8.67 h)	72.6° 22:10	11.51	35%	137.9°
2046-12-22 Sat	100	—	unknown	18:35–03:15 (good, 8.67 h)	72.6° 22:05	11.51	25%	152.2°
2046-12-23 Sun	100	—	unknown	18:40–03:10 (good, 8.5 h)	72.6° 22:00	11.51	15%	166.5°
2046-12-24 Mon	100	—	unknown	18:40–03:05 (good, 8.42 h)	72.6° 21:55	11.5	8%	179.2°
2046-12-25 Tue	100	—	unknown	18:40–03:05 (good, 8.42 h)	72.6° 21:50	11.5	3%	165.0°
2046-12-26 Wed	100	—	unknown	18:40–03:00 (good, 8.33 h)	72.6° 21:50	11.5	0%	151.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-11-27&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.