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: 10-17 (100), 10-18 (100), 10-19 (100), 10-20 (100), 10-21 (100) — by astronomy; check the weather when the night is within four days.

2047-10-17astronomy score per night — click a bar for that night2047-11-15

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-10-17 Thu	100	—	unknown	20:10–06:05 (good, 9.92 h)	79.2° 01:10	9.9	2%	150.8°
2047-10-18 Fri	100	—	unknown	20:10–06:05 (good, 9.92 h)	79.2° 01:10	9.95	0%	162.0°
2047-10-19 Sat	100	—	unknown	20:10–06:10 (good, 10.0 h)	79.2° 01:05	9.99	1%	164.5°
2047-10-20 Sun	100	—	unknown	20:10–06:10 (good, 10.0 h)	79.2° 01:00	10.03	5%	155.4°
2047-10-21 Mon	100	—	unknown	20:05–06:10 (good, 10.08 h)	79.2° 00:55	10.07	11%	142.5°
2047-10-22 Tue	100	—	unknown	20:05–06:10 (good, 10.08 h)	79.2° 00:55	10.11	20%	128.8°
2047-10-23 Wed	100	—	unknown	20:05–06:15 (good, 10.17 h)	79.2° 00:50	10.15	30%	115.1°
2047-10-24 Thu	100	—	unknown	20:00–06:15 (good, 10.25 h)	79.2° 00:45	10.19	40%	101.7°
2047-10-25 Fri	100	—	unknown	20:00–06:15 (good, 10.25 h)	79.2° 00:40	10.23	51%	88.7°
2047-10-26 Sat	100	—	unknown	20:00–05:10 (good, 10.17 h)	79.2° 00:35	10.27	62%	76.0°
2047-10-27 Sun	100	—	unknown	19:45–05:05 (good, 9.33 h)	79.2° 23:35	10.31	71%	63.7°
2047-10-28 Mon	94	—	unknown	23:05–05:00 (good, 5.92 h)	79.2° 23:30	10.35	80%	51.8°
2047-10-29 Tue	86	—	unknown	03:35–05:00 (good, 1.42 h)	79.2° 23:25	10.39	87%	40.3°
2047-10-30 Wed	71	—	unknown	04:35–04:55 (good, 0.33 h)	79.2° 23:20	10.42	93%	29.5°
2047-10-31 Thu	37	—	unknown	00:15–05:00 (marginal, 4.75 h)	79.2° 23:15	10.46	97%	20.1°
2047-11-01 Fri	28	—	unknown	02:10–04:40 (marginal, 2.5 h)	79.2° 23:15	10.5	99%	14.9°
2047-11-02 Sat	29	—	unknown	18:50–21:25 (marginal, 2.58 h)	79.2° 23:10	10.53	100%	17.8°
2047-11-03 Sun	33	—	unknown	18:50–22:15 (marginal, 3.42 h)	79.2° 23:05	10.57	99%	26.2°
2047-11-04 Mon	48	—	unknown	18:50–01:05 (marginal, 6.25 h)	79.2° 23:00	10.61	96%	36.4°
2047-11-05 Tue	60	—	unknown	19:05–20:20 (good, 1.25 h)	79.2° 23:00	10.64	91%	47.4°
2047-11-06 Wed	93	—	unknown	18:45–23:10 (good, 4.42 h)	79.2° 22:55	10.67	85%	58.7°
2047-11-07 Thu	100	—	unknown	18:45–02:00 (good, 7.25 h)	79.2° 22:50	10.71	77%	70.3°
2047-11-08 Fri	100	—	unknown	18:45–03:25 (good, 8.67 h)	79.2° 22:45	10.74	69%	82.1°
2047-11-09 Sat	100	—	unknown	18:45–03:55 (good, 9.17 h)	79.2° 22:40	10.77	59%	94.2°
2047-11-10 Sun	100	—	unknown	18:45–04:00 (good, 9.25 h)	79.2° 22:40	10.81	49%	106.6°
2047-11-11 Mon	100	—	unknown	18:45–04:00 (good, 9.25 h)	79.2° 22:35	10.84	38%	119.3°
2047-11-12 Tue	100	—	unknown	18:40–04:00 (good, 9.33 h)	79.2° 22:30	10.87	28%	132.3°
2047-11-13 Wed	100	—	unknown	18:40–03:55 (good, 9.25 h)	79.2° 22:25	10.9	18%	145.3°
2047-11-14 Thu	100	—	unknown	18:40–03:55 (good, 9.25 h)	79.2° 22:20	10.93	10%	157.5°
2047-11-15 Fri	100	—	unknown	18:40–03:50 (good, 9.17 h)	79.2° 22:20	10.96	4%	165.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-10-17&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.