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: 12-15 (100), 12-16 (100), 12-17 (100), 12-18 (100), 12-19 (100) — by astronomy; check the weather when the night is within four days.

2047-12-15astronomy score per night — click a bar for that night2048-01-13

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-12-15 Sun	100	—	unknown	18:35–01:55 (good, 7.33 h)	79.2° 20:20	11.49	2%	141.2°
2047-12-16 Mon	100	—	unknown	18:35–01:50 (good, 7.25 h)	79.2° 20:15	11.5	0%	127.1°
2047-12-17 Tue	100	—	unknown	18:35–01:45 (good, 7.17 h)	79.2° 20:10	11.5	1%	112.8°
2047-12-18 Wed	100	—	unknown	18:35–01:40 (good, 7.08 h)	79.2° 20:10	11.5	5%	98.6°
2047-12-19 Thu	100	—	unknown	18:35–01:35 (good, 7.0 h)	79.2° 20:05	11.51	12%	84.8°
2047-12-20 Fri	100	—	unknown	18:35–01:35 (good, 7.0 h)	79.2° 20:00	11.51	20%	71.5°
2047-12-21 Sat	100	—	unknown	18:35–01:30 (good, 6.92 h)	79.2° 19:55	11.51	29%	58.7°
2047-12-22 Sun	92	—	unknown	18:35–01:25 (good, 6.83 h)	79.2° 19:55	11.51	39%	46.5°
2047-12-23 Mon	84	—	unknown	18:40–01:20 (good, 6.67 h)	79.2° 19:50	11.51	48%	35.0°
2047-12-24 Tue	64	—	unknown	20:55–00:35 (good, 3.67 h)	79.2° 19:45	11.5	58%	24.6°
2047-12-25 Wed	50	—	unknown	18:40–01:40 (marginal, 7.0 h)	79.2° 19:40	11.5	68%	16.6°
2047-12-26 Thu	35	—	unknown	18:40–01:25 (marginal, 6.75 h)	79.2° 19:35	11.5	76%	15.1°
2047-12-27 Fri	25	—	unknown	18:40–01:00 (marginal, 6.33 h)	79.2° 19:35	11.49	84%	21.3°
2047-12-28 Sat	21	—	unknown	18:40–22:15 (marginal, 3.58 h)	79.2° 19:30	11.49	90%	30.9°
2047-12-29 Sun	26	—	unknown	18:40–23:30 (marginal, 4.83 h)	79.2° 19:25	11.48	95%	41.7°
2047-12-30 Mon	36	—	unknown	18:40–00:30 (marginal, 5.83 h)	79.2° 19:20	11.47	98%	52.9°
2047-12-31 Tue	50	—	unknown	18:45–19:05 (good, 0.33 h)	79.2° 19:15	11.46	100%	64.6°
2048-01-01 Wed	68	—	unknown	18:45–21:40 (good, 2.92 h)	79.2° 19:15	11.45	100%	76.4°
2048-01-02 Thu	80	—	unknown	18:45–23:00 (good, 4.25 h)	79.2° 19:10	11.44	97%	88.5°
2048-01-03 Fri	100	—	unknown	18:45–00:10 (good, 5.42 h)	79.2° 19:05	11.43	93%	100.8°
2048-01-04 Sat	100	—	unknown	18:45–00:20 (good, 5.58 h)	79.2° 19:00	11.42	87%	113.2°
2048-01-05 Sun	100	—	unknown	18:45–00:20 (good, 5.58 h)	79.2° 19:00	11.41	79%	125.7°
2048-01-06 Mon	100	—	unknown	18:50–00:20 (good, 5.5 h)	79.2° 18:55	11.39	70%	138.2°
2048-01-07 Tue	100	—	unknown	18:50–00:20 (good, 5.5 h)	79.2° 18:50	11.38	59%	150.3°
2048-01-08 Wed	100	—	unknown	18:50–00:20 (good, 5.5 h)	79.2° 18:45	11.36	48%	161.0°
2048-01-09 Thu	100	—	unknown	18:50–00:15 (good, 5.42 h)	79.2° 18:40	11.35	37%	165.3°
2048-01-10 Fri	100	—	unknown	18:50–00:10 (good, 5.33 h)	79.2° 18:40	11.33	26%	158.4°
2048-01-11 Sat	100	—	unknown	18:50–00:05 (good, 5.25 h)	79.2° 18:35	11.31	17%	146.4°
2048-01-12 Sun	100	—	unknown	18:55–00:05 (good, 5.17 h)	79.2° 18:30	11.29	9%	132.9°
2048-01-13 Mon	100	—	unknown	18:55–00:00 (good, 5.08 h)	79.2° 18:25	11.27	3%	119.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-12-15&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.