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 Triangulum Pinwheel: 12-16 (100), 12-27 (100), 12-28 (100), 12-29 (100), 12-30 (100) — by astronomy; check the weather when the night is within four days.

2034-12-16astronomy score per night — click a bar for that night2035-01-14

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-12-16 Sat	100	—	unknown	18:35–01:45 (good, 7.17 h)	79.1° 20:15	11.5	31%	61.4°
2034-12-17 Sun	94	—	unknown	18:35–01:45 (good, 7.17 h)	79.1° 20:10	11.5	41%	50.0°
2034-12-18 Mon	85	—	unknown	18:35–01:40 (good, 7.08 h)	79.1° 20:05	11.5	52%	39.0°
2034-12-19 Tue	62	—	unknown	21:55–23:55 (good, 2.0 h)	79.1° 20:05	11.51	63%	29.3°
2034-12-20 Wed	46	—	unknown	18:35–01:55 (marginal, 7.33 h)	79.1° 20:00	11.51	74%	23.3°
2034-12-21 Thu	32	—	unknown	18:35–01:35 (marginal, 7.0 h)	79.1° 19:55	11.51	83%	24.8°
2034-12-22 Fri	27	—	unknown	18:35–01:05 (marginal, 6.5 h)	79.1° 19:50	11.51	91%	33.2°
2034-12-23 Sat	34	—	unknown	18:40–00:55 (marginal, 6.25 h)	79.1° 19:45	11.51	97%	45.0°
2034-12-24 Sun	48	—	unknown	18:40–01:05 (marginal, 6.42 h)	79.1° 19:45	11.5	100%	58.1°
2034-12-25 Mon	70	—	unknown	18:40–21:05 (good, 2.42 h)	79.1° 19:40	11.5	99%	71.8°
2034-12-26 Tue	80	—	unknown	18:40–23:10 (good, 4.5 h)	79.1° 19:35	11.5	96%	85.4°
2034-12-27 Wed	100	—	unknown	18:40–00:35 (good, 5.92 h)	79.1° 19:30	11.49	91%	98.8°
2034-12-28 Thu	100	—	unknown	18:40–00:45 (good, 6.08 h)	79.1° 19:30	11.48	83%	111.6°
2034-12-29 Fri	100	—	unknown	18:40–00:50 (good, 6.17 h)	79.1° 19:25	11.48	74%	123.8°
2034-12-30 Sat	100	—	unknown	18:40–00:45 (good, 6.08 h)	79.1° 19:20	11.47	65%	135.1°
2034-12-31 Sun	100	—	unknown	18:45–00:45 (good, 6.0 h)	79.1° 19:15	11.46	55%	145.1°
2035-01-01 Mon	100	—	unknown	18:45–00:45 (good, 6.0 h)	79.1° 19:10	11.45	45%	153.0°
2035-01-02 Tue	100	—	unknown	18:45–00:40 (good, 5.92 h)	79.1° 19:10	11.44	36%	156.9°
2035-01-03 Wed	100	—	unknown	18:45–00:35 (good, 5.83 h)	79.1° 19:05	11.43	27%	155.3°
2035-01-04 Thu	100	—	unknown	18:45–00:35 (good, 5.83 h)	79.1° 19:00	11.42	19%	149.1°
2035-01-05 Fri	100	—	unknown	18:45–00:30 (good, 5.75 h)	79.1° 18:55	11.4	12%	140.5°
2035-01-06 Sat	100	—	unknown	18:50–00:25 (good, 5.58 h)	79.1° 18:50	11.39	7%	130.7°
2035-01-07 Sun	100	—	unknown	18:50–00:20 (good, 5.5 h)	79.1° 18:50	11.38	3%	120.3°
2035-01-08 Mon	100	—	unknown	18:50–00:15 (good, 5.42 h)	79.1° 18:45	11.36	1%	109.5°
2035-01-09 Tue	100	—	unknown	18:50–00:15 (good, 5.42 h)	79.1° 18:40	11.34	0%	98.3°
2035-01-10 Wed	100	—	unknown	18:50–00:10 (good, 5.33 h)	79.1° 18:35	11.33	2%	87.0°
2035-01-11 Thu	100	—	unknown	18:50–00:05 (good, 5.25 h)	79.1° 18:35	11.31	5%	75.5°
2035-01-12 Fri	100	—	unknown	18:55–00:00 (good, 5.08 h)	79.1° 18:30	11.29	11%	64.0°
2035-01-13 Sat	97	—	unknown	18:55–23:55 (good, 5.0 h)	79.1° 18:25	11.27	18%	52.5°
2035-01-14 Sun	88	—	unknown	18:55–23:55 (good, 5.0 h)	79.1° 18:20	11.25	26%	41.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-12-16&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.