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: 12-11 (100), 12-12 (100), 12-13 (100), 12-14 (100), 12-15 (100) — by astronomy; check the weather when the night is within four days.

2036-12-11astronomy score per night — click a bar for that night2037-01-09

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2036-12-11 Thu	100	—	unknown	18:35–02:05 (good, 7.5 h)	79.1° 20:35	11.47	33%	147.2°
2036-12-12 Fri	100	—	unknown	18:35–02:00 (good, 7.42 h)	79.2° 20:30	11.48	23%	154.0°
2036-12-13 Sat	100	—	unknown	18:35–01:55 (good, 7.33 h)	79.2° 20:25	11.48	15%	155.1°
2036-12-14 Sun	100	—	unknown	18:35–01:55 (good, 7.33 h)	79.2° 20:20	11.49	8%	150.0°
2036-12-15 Mon	100	—	unknown	18:35–01:50 (good, 7.25 h)	79.1° 20:15	11.49	3%	141.3°
2036-12-16 Tue	100	—	unknown	18:35–01:45 (good, 7.17 h)	79.1° 20:15	11.5	1%	130.9°
2036-12-17 Wed	100	—	unknown	18:35–01:40 (good, 7.08 h)	79.2° 20:10	11.5	0%	120.0°
2036-12-18 Thu	100	—	unknown	18:35–01:40 (good, 7.08 h)	79.2° 20:05	11.5	2%	108.9°
2036-12-19 Fri	100	—	unknown	18:35–01:35 (good, 7.0 h)	79.2° 20:00	11.51	5%	97.8°
2036-12-20 Sat	100	—	unknown	18:35–01:30 (good, 6.92 h)	79.1° 19:55	11.51	10%	86.8°
2036-12-21 Sun	100	—	unknown	18:35–01:25 (good, 6.83 h)	79.2° 19:55	11.51	16%	76.0°
2036-12-22 Mon	100	—	unknown	18:35–01:20 (good, 6.75 h)	79.2° 19:50	11.51	24%	65.3°
2036-12-23 Tue	98	—	unknown	18:40–01:20 (good, 6.67 h)	79.2° 19:45	11.5	32%	55.0°
2036-12-24 Wed	90	—	unknown	18:40–01:15 (good, 6.58 h)	79.2° 19:40	11.5	42%	45.0°
2036-12-25 Thu	82	—	unknown	18:40–01:10 (good, 6.5 h)	79.1° 19:40	11.5	51%	35.9°
2036-12-26 Fri	62	—	unknown	21:15–23:15 (good, 2.0 h)	79.2° 19:35	11.49	61%	28.5°
2036-12-27 Sat	46	—	unknown	18:40–01:25 (marginal, 6.75 h)	79.2° 19:30	11.49	70%	24.7°
2036-12-28 Sun	32	—	unknown	18:40–01:05 (marginal, 6.42 h)	79.2° 19:25	11.48	79%	26.6°
2036-12-29 Mon	27	—	unknown	18:40–00:45 (marginal, 6.08 h)	79.1° 19:20	11.47	87%	33.7°
2036-12-30 Tue	30	—	unknown	18:40–00:30 (marginal, 5.83 h)	79.1° 19:20	11.47	94%	43.9°
2036-12-31 Wed	39	—	unknown	18:45–00:35 (marginal, 5.83 h)	79.2° 19:15	11.46	98%	55.8°
2037-01-01 Thu	55	—	unknown	18:45–19:45 (good, 1.0 h)	79.2° 19:10	11.45	100%	68.6°
2037-01-02 Fri	75	—	unknown	18:45–22:10 (good, 3.42 h)	79.2° 19:05	11.44	99%	81.9°
2037-01-03 Sat	100	—	unknown	18:45–23:40 (good, 4.92 h)	79.1° 19:00	11.42	95%	95.5°
2037-01-04 Sun	100	—	unknown	18:45–00:10 (good, 5.42 h)	79.2° 19:00	11.41	89%	108.9°
2037-01-05 Mon	100	—	unknown	18:45–00:20 (good, 5.58 h)	79.2° 18:55	11.4	80%	122.0°
2037-01-06 Tue	100	—	unknown	18:50–00:15 (good, 5.42 h)	79.2° 18:50	11.38	70%	134.2°
2037-01-07 Wed	100	—	unknown	18:50–00:15 (good, 5.42 h)	79.2° 18:45	11.37	59%	145.0°
2037-01-08 Thu	100	—	unknown	18:50–00:15 (good, 5.42 h)	79.1° 18:45	11.35	48%	152.8°
2037-01-09 Fri	100	—	unknown	18:50–00:10 (good, 5.33 h)	79.2° 18:40	11.34	37%	155.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-12-11&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.