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: 11-16 (100), 11-17 (100), 11-18 (100), 11-19 (100), 11-20 (100) — by astronomy; check the weather when the night is within four days.

2038-11-10astronomy score per night — click a bar for that night2038-12-09

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2038-11-10 Wed	33	—	unknown	18:45–21:45 (marginal, 3.0 h)	79.2° 22:35	10.81	99%	23.9°
2038-11-11 Thu	33	—	unknown	18:45–21:50 (marginal, 3.08 h)	79.2° 22:35	10.84	100%	27.9°
2038-11-12 Fri	42	—	unknown	18:40–23:20 (marginal, 4.67 h)	79.2° 22:30	10.87	99%	35.3°
2038-11-13 Sat	57	—	unknown	18:40–03:20 (marginal, 8.67 h)	79.2° 22:25	10.9	96%	44.5°
2038-11-14 Sun	91	—	unknown	18:40–21:10 (good, 2.5 h)	79.2° 22:20	10.93	92%	54.6°
2038-11-15 Mon	97	—	unknown	18:40–23:50 (good, 5.17 h)	79.2° 22:15	10.96	86%	65.3°
2038-11-16 Tue	100	—	unknown	18:40–01:50 (good, 7.17 h)	79.2° 22:15	10.99	79%	76.4°
2038-11-17 Wed	100	—	unknown	18:40–03:10 (good, 8.5 h)	79.2° 22:10	11.02	70%	87.8°
2038-11-18 Thu	100	—	unknown	18:40–03:20 (good, 8.67 h)	79.2° 22:05	11.04	60%	99.4°
2038-11-19 Fri	100	—	unknown	18:35–03:25 (good, 8.83 h)	79.2° 22:00	11.07	50%	111.3°
2038-11-20 Sat	100	—	unknown	18:35–03:25 (good, 8.83 h)	79.2° 21:55	11.1	39%	123.3°
2038-11-21 Sun	100	—	unknown	18:35–03:25 (good, 8.83 h)	79.2° 21:55	11.12	29%	135.1°
2038-11-22 Mon	100	—	unknown	18:35–03:20 (good, 8.75 h)	79.2° 21:50	11.15	19%	146.1°
2038-11-23 Tue	100	—	unknown	18:35–03:20 (good, 8.75 h)	79.2° 21:45	11.17	10%	154.2°
2038-11-24 Wed	100	—	unknown	18:35–03:15 (good, 8.67 h)	79.2° 21:40	11.19	4%	155.8°
2038-11-25 Thu	100	—	unknown	18:35–03:10 (good, 8.58 h)	79.2° 21:40	11.21	1%	149.3°
2038-11-26 Fri	100	—	unknown	18:35–03:05 (good, 8.5 h)	79.2° 21:35	11.24	0%	138.4°
2038-11-27 Sat	100	—	unknown	18:35–03:00 (good, 8.42 h)	79.2° 21:30	11.26	3%	125.8°
2038-11-28 Sun	100	—	unknown	18:35–03:00 (good, 8.42 h)	79.2° 21:25	11.28	8%	112.7°
2038-11-29 Mon	100	—	unknown	18:35–02:55 (good, 8.33 h)	79.2° 21:20	11.3	15%	99.7°
2038-11-30 Tue	100	—	unknown	18:35–02:50 (good, 8.25 h)	79.2° 21:20	11.31	24%	87.1°
2038-12-01 Wed	100	—	unknown	18:35–02:45 (good, 8.17 h)	79.2° 21:15	11.33	34%	74.9°
2038-12-02 Thu	100	—	unknown	18:35–02:45 (good, 8.17 h)	79.2° 21:10	11.35	44%	63.2°
2038-12-03 Fri	95	—	unknown	18:35–02:40 (good, 8.08 h)	79.2° 21:05	11.37	54%	52.2°
2038-12-04 Sat	87	—	unknown	18:35–02:35 (good, 8.0 h)	79.2° 21:00	11.38	64%	42.0°
2038-12-05 Sun	73	—	unknown	02:10–02:30 (good, 0.33 h)	79.2° 21:00	11.39	72%	33.1°
2038-12-06 Mon	47	—	unknown	18:35–02:45 (marginal, 8.17 h)	79.2° 20:55	11.41	80%	26.4°
2038-12-07 Tue	35	—	unknown	18:35–02:30 (marginal, 7.92 h)	79.2° 20:50	11.42	87%	23.8°
2038-12-08 Wed	29	—	unknown	18:35–02:05 (marginal, 7.5 h)	79.2° 20:45	11.43	93%	26.5°
2038-12-09 Thu	28	—	unknown	18:35–21:30 (marginal, 2.92 h)	79.2° 20:45	11.44	97%	33.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2038-11-10&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.