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: 11-27 (100), 11-28 (100), 11-29 (100), 11-30 (100), 12-01 (100) — by astronomy; check the weather when the night is within four days.

2038-11-27astronomy score per night — click a bar for that night2038-12-26

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2038-12-10 Fri	36	—	unknown	18:35–23:40 (marginal, 5.08 h)	79.2° 20:40	11.45	99%	42.0°
2038-12-11 Sat	50	—	unknown	18:35–01:40 (marginal, 7.08 h)	79.2° 20:35	11.46	100%	52.0°
2038-12-12 Sun	67	—	unknown	18:35–20:05 (good, 1.5 h)	79.2° 20:30	11.47	99%	62.7°
2038-12-13 Mon	76	—	unknown	18:35–22:50 (good, 4.25 h)	79.2° 20:25	11.48	96%	73.8°
2038-12-14 Tue	100	—	unknown	18:35–00:15 (good, 5.67 h)	79.2° 20:25	11.49	90%	85.2°
2038-12-15 Wed	100	—	unknown	18:35–01:25 (good, 6.83 h)	79.2° 20:20	11.49	84%	96.8°
2038-12-16 Thu	100	—	unknown	18:35–01:30 (good, 6.92 h)	79.2° 20:15	11.5	75%	108.5°
2038-12-17 Fri	100	—	unknown	18:35–01:35 (good, 7.0 h)	79.2° 20:10	11.5	66%	120.3°
2038-12-18 Sat	100	—	unknown	18:35–01:35 (good, 7.0 h)	79.2° 20:05	11.5	55%	131.9°
2038-12-19 Sun	100	—	unknown	18:35–01:30 (good, 6.92 h)	79.2° 20:05	11.51	44%	142.8°
2038-12-20 Mon	100	—	unknown	18:35–01:30 (good, 6.92 h)	79.2° 20:00	11.51	33%	151.9°
2038-12-21 Tue	100	—	unknown	18:35–01:30 (good, 6.92 h)	79.2° 19:55	11.51	23%	156.2°
2038-12-22 Wed	100	—	unknown	18:35–01:25 (good, 6.83 h)	79.2° 19:50	11.51	14%	152.7°
2038-12-23 Thu	100	—	unknown	18:40–01:20 (good, 6.67 h)	79.2° 19:50	11.51	6%	143.5°
2038-12-24 Fri	100	—	unknown	18:40–01:15 (good, 6.58 h)	79.2° 19:45	11.5	2%	131.6°
2038-12-25 Sat	100	—	unknown	18:40–01:10 (good, 6.5 h)	79.2° 19:40	11.5	0%	118.7°
2038-12-26 Sun	100	—	unknown	18:40–01:10 (good, 6.5 h)	79.2° 19:35	11.5	1%	105.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2038-11-27&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.