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: 01-02 (100), 01-03 (100), 01-04 (100), 01-05 (100), 01-06 (100) — by astronomy; check the weather when the night is within four days.

2030-01-02astronomy score per night — click a bar for that night2030-01-31

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2030-01-02 Wed	100	—	unknown	18:45–00:40 (good, 5.92 h)	79.1° 19:05	11.44	2%	124.2°
2030-01-03 Thu	100	—	unknown	18:45–00:35 (good, 5.83 h)	79.1° 19:05	11.43	0%	110.3°
2030-01-04 Fri	100	—	unknown	18:45–00:30 (good, 5.75 h)	79.1° 19:00	11.42	1%	96.5°
2030-01-05 Sat	100	—	unknown	18:45–00:30 (good, 5.75 h)	79.1° 18:55	11.4	4%	83.1°
2030-01-06 Sun	100	—	unknown	18:50–00:25 (good, 5.58 h)	79.1° 18:50	11.39	10%	70.0°
2030-01-07 Mon	100	—	unknown	18:50–00:20 (good, 5.5 h)	79.1° 18:45	11.37	17%	57.4°
2030-01-08 Tue	92	—	unknown	18:50–00:15 (good, 5.42 h)	79.1° 18:45	11.36	25%	45.4°
2030-01-09 Wed	83	—	unknown	18:50–00:10 (good, 5.33 h)	79.1° 18:40	11.34	34%	34.1°
2030-01-10 Thu	72	—	unknown	18:50–23:50 (good, 5.0 h)	79.1° 18:35	11.32	44%	24.0°
2030-01-11 Fri	56	—	unknown	18:50–22:35 (good, 3.75 h)	79.1° 18:30	11.3	53%	16.6°
2030-01-12 Sat	41	—	unknown	18:55–00:20 (marginal, 5.42 h)	79.1° 18:30	11.29	63%	16.0°
2030-01-13 Sun	29	—	unknown	18:55–00:05 (marginal, 5.17 h)	79.1° 18:25	11.27	71%	22.6°
2030-01-14 Mon	22	—	unknown	18:55–23:45 (marginal, 4.83 h)	79.1° 18:20	11.25	80%	32.2°
2030-01-15 Tue	23	—	unknown	18:55–23:35 (marginal, 4.67 h)	79.1° 18:15	11.22	87%	43.1°
2030-01-16 Wed	29	—	unknown	18:55–23:35 (marginal, 4.67 h)	79.1° 18:10	11.2	93%	54.5°
2030-01-17 Thu	37	—	unknown	19:00–23:40 (marginal, 4.67 h)	79.1° 18:10	11.18	97%	66.4°
2030-01-18 Fri	50	—	unknown	19:00–20:45 (good, 1.75 h)	79.1° 18:05	11.16	99%	78.6°
2030-01-19 Sat	65	—	unknown	19:00–22:00 (good, 3.0 h)	79.1° 18:00	11.13	100%	91.0°
2030-01-20 Sun	80	—	unknown	19:00–23:05 (good, 4.08 h)	79.1° 17:55	11.11	98%	103.7°
2030-01-21 Mon	100	—	unknown	19:00–23:10 (good, 4.17 h)	79.1° 17:50	11.08	94%	116.6°
2030-01-22 Tue	100	—	unknown	19:05–23:10 (good, 4.08 h)	79.1° 17:50	11.05	88%	129.5°
2030-01-23 Wed	100	—	unknown	19:05–23:10 (good, 4.08 h)	79.1° 17:45	11.03	80%	142.2°
2030-01-24 Thu	100	—	unknown	19:05–23:15 (good, 4.17 h)	79.1° 17:40	11.0	70%	154.2°
2030-01-25 Fri	100	—	unknown	19:05–23:10 (good, 4.08 h)	79.1° 17:35	10.97	59%	163.2°
2030-01-26 Sat	100	—	unknown	19:10–23:05 (good, 3.92 h)	79.1° 17:35	10.94	48%	163.2°
2030-01-27 Sun	100	—	unknown	19:10–23:00 (good, 3.83 h)	79.1° 17:30	10.91	37%	154.1°
2030-01-28 Mon	99	—	unknown	19:10–22:55 (good, 3.75 h)	79.1° 17:25	10.88	26%	141.9°
2030-01-29 Tue	97	—	unknown	19:10–22:55 (good, 3.75 h)	79.1° 17:20	10.85	17%	128.7°
2030-01-30 Wed	96	—	unknown	19:10–22:50 (good, 3.67 h)	79.1° 17:15	10.82	9%	115.3°
2030-01-31 Thu	93	—	unknown	19:15–22:45 (good, 3.5 h)	79.1° 17:15	10.79	4%	101.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2030-01-02&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.