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: 02-04 (86), 02-05 (82), 02-06 (80), 02-07 (78), 02-08 (76) — by astronomy; check the weather when the night is within four days.

2035-02-04astronomy score per night — click a bar for that night2035-03-05

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2035-02-04 Sun	86	—	unknown	19:15–22:30 (good, 3.25 h)	79.1° 17:00	10.66	11%	112.8°
2035-02-05 Mon	82	—	unknown	19:20–22:25 (good, 3.08 h)	79.1° 16:55	10.63	6%	101.7°
2035-02-06 Tue	80	—	unknown	19:20–22:25 (good, 3.08 h)	79.1° 16:50	10.59	2%	90.3°
2035-02-07 Wed	78	—	unknown	19:20–22:20 (good, 3.0 h)	79.1° 16:45	10.56	0%	78.8°
2035-02-08 Thu	76	—	unknown	19:20–22:15 (good, 2.92 h)	79.1° 16:45	10.52	0%	67.1°
2035-02-09 Fri	72	—	unknown	19:25–22:10 (good, 2.75 h)	79.1° 16:40	10.48	3%	55.4°
2035-02-10 Sat	67	—	unknown	19:25–22:05 (good, 2.67 h)	79.1° 16:35	10.45	7%	44.1°
2035-02-11 Sun	59	—	unknown	19:25–22:05 (good, 2.67 h)	79.1° 16:30	10.41	14%	33.7°
2035-02-12 Mon	50	—	unknown	19:25–21:50 (good, 2.42 h)	79.1° 16:25	10.37	22%	25.8°
2035-02-13 Tue	40	—	unknown	19:25–21:40 (good, 2.25 h)	79.1° 16:25	10.33	32%	23.4°
2035-02-14 Wed	30	—	unknown	19:30–21:00 (good, 1.5 h)	79.1° 16:20	10.29	43%	28.1°
2035-02-15 Thu	23	—	unknown	19:30–22:10 (marginal, 2.67 h)	79.1° 16:15	10.25	54%	37.5°
2035-02-16 Fri	19	—	unknown	19:30–22:00 (marginal, 2.5 h)	79.1° 16:10	10.21	66%	49.1°
2035-02-17 Sat	19	—	unknown	19:30–21:55 (marginal, 2.42 h)	79.1° 16:05	10.17	76%	61.6°
2035-02-18 Sun	19	—	unknown	19:35–21:50 (marginal, 2.25 h)	79.1° 16:05	10.13	85%	74.6°
2035-02-19 Mon	23	—	unknown	19:35–19:55 (good, 0.33 h)	79.1° 16:00	10.09	92%	87.7°
2035-02-20 Tue	27	—	unknown	19:35–20:55 (good, 1.33 h)	79.1° 15:55	10.05	97%	100.7°
2035-02-21 Wed	33	—	unknown	19:35–21:05 (good, 1.5 h)	79.1° 15:50	10.01	100%	113.5°
2035-02-22 Thu	34	—	unknown	19:40–21:10 (good, 1.5 h)	79.1° 15:50	9.96	100%	125.7°
2035-02-23 Fri	35	—	unknown	19:40–21:05 (good, 1.42 h)	79.1° 15:45	9.92	97%	137.1°
2035-02-24 Sat	37	—	unknown	19:40–21:05 (good, 1.42 h)	79.1° 15:40	9.88	92%	147.1°
2035-02-25 Sun	37	—	unknown	19:40–21:10 (good, 1.5 h)	79.1° 15:35	9.83	86%	154.3°
2035-02-26 Mon	36	—	unknown	19:40–21:05 (good, 1.42 h)	79.1° 15:30	9.79	79%	156.7°
2035-02-27 Tue	33	—	unknown	19:45–21:00 (good, 1.25 h)	79.1° 15:30	9.75	70%	153.3°
2035-02-28 Wed	32	—	unknown	19:45–20:55 (good, 1.17 h)	79.1° 15:25	9.7	61%	146.0°
2035-03-01 Thu	29	—	unknown	19:45–20:50 (good, 1.08 h)	79.1° 15:20	9.66	52%	136.9°
2035-03-02 Fri	28	—	unknown	19:45–20:50 (good, 1.08 h)	79.1° 15:15	9.61	42%	126.9°
2035-03-03 Sat	26	—	unknown	19:50–20:45 (good, 0.92 h)	79.1° 15:10	9.56	33%	116.4°
2035-03-04 Sun	25	—	unknown	19:50–20:40 (good, 0.83 h)	79.1° 15:10	9.52	24%	105.6°
2035-03-05 Mon	23	—	unknown	19:50–20:35 (good, 0.75 h)	79.1° 15:05	9.47	17%	94.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-02-04&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.