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: 02-09 (71), 02-10 (69), 02-11 (66), 02-12 (64), 02-13 (61) — by astronomy; check the weather when the night is within four days.

2045-02-09astronomy score per night — click a bar for that night2045-03-10

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2045-02-09 Thu	71	—	unknown	19:25–22:10 (good, 2.75 h)	79.2° 16:35	10.46	39%	146.3°
2045-02-10 Fri	69	—	unknown	19:25–22:05 (good, 2.67 h)	79.2° 16:35	10.42	30%	135.2°
2045-02-11 Sat	66	—	unknown	19:25–22:00 (good, 2.58 h)	79.2° 16:30	10.39	21%	123.9°
2045-02-12 Sun	64	—	unknown	19:25–22:00 (good, 2.58 h)	79.2° 16:25	10.35	14%	112.6°
2045-02-13 Mon	61	—	unknown	19:30–21:55 (good, 2.42 h)	79.2° 16:20	10.31	8%	101.2°
2045-02-14 Tue	60	—	unknown	19:30–21:50 (good, 2.33 h)	79.2° 16:15	10.27	4%	89.8°
2045-02-15 Wed	57	—	unknown	19:30–21:45 (good, 2.25 h)	79.2° 16:15	10.23	1%	78.3°
2045-02-16 Thu	55	—	unknown	19:30–21:40 (good, 2.17 h)	79.2° 16:10	10.19	0%	66.8°
2045-02-17 Fri	52	—	unknown	19:35–21:40 (good, 2.08 h)	79.2° 16:05	10.15	1%	55.2°
2045-02-18 Sat	50	—	unknown	19:35–21:35 (good, 2.0 h)	79.2° 16:00	10.11	4%	43.7°
2045-02-19 Sun	45	—	unknown	19:35–21:30 (good, 1.92 h)	79.2° 16:00	10.07	8%	32.5°
2045-02-20 Mon	40	—	unknown	19:35–21:20 (good, 1.75 h)	79.2° 15:55	10.02	14%	22.2°
2045-02-21 Tue	33	—	unknown	19:35–21:10 (good, 1.58 h)	79.2° 15:50	9.98	22%	15.2°
2045-02-22 Wed	26	—	unknown	19:40–21:00 (good, 1.33 h)	79.2° 15:45	9.94	32%	17.2°
2045-02-23 Thu	20	—	unknown	19:40–20:00 (good, 0.33 h)	79.2° 15:40	9.9	42%	26.4°
2045-02-24 Fri	15	—	unknown	19:40–21:30 (marginal, 1.83 h)	79.2° 15:40	9.85	53%	38.3°
2045-02-25 Sat	13	—	unknown	19:40–21:20 (marginal, 1.67 h)	79.2° 15:35	9.81	64%	51.3°
2045-02-26 Sun	12	—	unknown	19:45–21:15 (marginal, 1.5 h)	79.2° 15:30	9.76	74%	65.0°
2045-02-27 Mon	13	—	unknown	19:45–21:15 (marginal, 1.5 h)	79.2° 15:25	9.72	84%	79.0°
2045-02-28 Tue	15	—	unknown	19:45–19:50 (good, 0.08 h)	79.2° 15:20	9.67	92%	93.4°
2045-03-01 Wed	19	—	unknown	19:45–20:30 (good, 0.75 h)	79.2° 15:20	9.63	97%	107.8°
2045-03-02 Thu	21	—	unknown	19:50–20:35 (good, 0.75 h)	79.2° 15:15	9.58	100%	122.2°
2045-03-03 Fri	20	—	unknown	19:50–20:35 (good, 0.75 h)	79.2° 15:10	9.54	99%	136.2°
2045-03-04 Sat	22	—	unknown	19:50–20:30 (good, 0.67 h)	79.2° 15:05	9.49	96%	149.3°
2045-03-05 Sun	22	—	unknown	19:50–20:35 (good, 0.75 h)	79.2° 15:05	9.44	91%	160.4°
2045-03-06 Mon	21	—	unknown	19:50–20:30 (good, 0.67 h)	79.2° 15:00	9.4	84%	165.3°
2045-03-07 Tue	18	—	unknown	19:55–20:25 (good, 0.5 h)	79.2° 14:55	9.35	75%	160.0°
2045-03-08 Wed	17	—	unknown	19:55–20:25 (good, 0.5 h)	79.2° 14:50	9.3	66%	149.9°
2045-03-09 Thu	15	—	unknown	19:55–20:20 (good, 0.42 h)	79.2° 14:45	9.25	56%	138.7°
2045-03-10 Fri	14	—	unknown	19:55–20:15 (good, 0.33 h)	79.2° 14:45	9.2	46%	127.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2045-02-09&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.