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: 11-20 (100), 11-30 (100), 12-01 (100), 12-02 (100), 12-03 (100) — by astronomy; check the weather when the night is within four days.

2042-11-20astronomy score per night — click a bar for that night2042-12-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2042-11-20 Thu	100	—	unknown	18:35–03:30 (good, 8.92 h)	79.2° 21:55	11.1	54%	63.8°
2042-11-21 Fri	94	—	unknown	18:35–03:25 (good, 8.83 h)	79.2° 21:55	11.12	64%	50.8°
2042-11-22 Sat	84	—	unknown	23:45–03:20 (good, 3.58 h)	79.2° 21:50	11.15	75%	38.1°
2042-11-23 Sun	49	—	unknown	18:35–03:45 (marginal, 9.17 h)	79.2° 21:45	11.17	84%	26.3°
2042-11-24 Mon	32	—	unknown	18:35–03:20 (marginal, 8.75 h)	79.2° 21:40	11.19	92%	18.4°
2042-11-25 Tue	26	—	unknown	18:35–20:35 (marginal, 2.0 h)	79.2° 21:40	11.22	97%	20.5°
2042-11-26 Wed	26	—	unknown	18:35–20:55 (marginal, 2.33 h)	79.2° 21:35	11.24	100%	30.7°
2042-11-27 Thu	44	—	unknown	18:35–00:30 (marginal, 5.92 h)	79.2° 21:30	11.26	99%	43.4°
2042-11-28 Fri	64	—	unknown	18:35–20:05 (good, 1.5 h)	79.2° 21:25	11.28	96%	56.8°
2042-11-29 Sat	98	—	unknown	18:35–23:30 (good, 4.92 h)	79.2° 21:20	11.3	90%	70.2°
2042-11-30 Sun	100	—	unknown	18:35–01:20 (good, 6.75 h)	79.2° 21:20	11.32	83%	83.3°
2042-12-01 Mon	100	—	unknown	18:35–02:25 (good, 7.83 h)	79.2° 21:15	11.33	74%	96.0°
2042-12-02 Tue	100	—	unknown	18:35–02:30 (good, 7.92 h)	79.2° 21:10	11.35	64%	108.2°
2042-12-03 Wed	100	—	unknown	18:35–02:35 (good, 8.0 h)	79.2° 21:05	11.37	55%	120.0°
2042-12-04 Thu	100	—	unknown	18:35–02:30 (good, 7.92 h)	79.2° 21:00	11.38	45%	131.3°
2042-12-05 Fri	100	—	unknown	18:35–02:30 (good, 7.92 h)	79.2° 21:00	11.4	36%	142.0°
2042-12-06 Sat	100	—	unknown	18:35–02:25 (good, 7.83 h)	79.2° 20:55	11.41	27%	151.8°
2042-12-07 Sun	100	—	unknown	18:35–02:25 (good, 7.83 h)	79.2° 20:50	11.42	19%	159.5°
2042-12-08 Mon	100	—	unknown	18:35–02:20 (good, 7.75 h)	79.2° 20:45	11.43	12%	162.1°
2042-12-09 Tue	100	—	unknown	18:35–02:15 (good, 7.67 h)	79.2° 20:45	11.44	7%	157.9°
2042-12-10 Wed	100	—	unknown	18:35–02:10 (good, 7.58 h)	79.2° 20:40	11.45	3%	149.3°
2042-12-11 Thu	100	—	unknown	18:35–02:05 (good, 7.5 h)	79.2° 20:35	11.46	1%	139.0°
2042-12-12 Fri	100	—	unknown	18:35–02:05 (good, 7.5 h)	79.2° 20:30	11.47	0%	127.8°
2042-12-13 Sat	100	—	unknown	18:35–02:00 (good, 7.42 h)	79.2° 20:25	11.48	2%	116.1°
2042-12-14 Sun	100	—	unknown	18:35–01:55 (good, 7.33 h)	79.2° 20:25	11.49	6%	104.0°
2042-12-15 Mon	100	—	unknown	18:35–01:50 (good, 7.25 h)	79.2° 20:20	11.49	11%	91.7°
2042-12-16 Tue	100	—	unknown	18:35–01:50 (good, 7.25 h)	79.2° 20:15	11.5	19%	79.2°
2042-12-17 Wed	100	—	unknown	18:35–01:45 (good, 7.17 h)	79.2° 20:10	11.5	28%	66.5°
2042-12-18 Thu	97	—	unknown	18:35–01:40 (good, 7.08 h)	79.2° 20:05	11.5	38%	53.8°
2042-12-19 Fri	87	—	unknown	18:35–01:35 (good, 7.0 h)	79.2° 20:05	11.51	49%	41.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2042-11-20&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.