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: 02-28 (32), 03-01 (29), 03-02 (28), 03-03 (26), 03-04 (25) — by astronomy; check the weather when the night is within four days.

2035-02-28astronomy score per night — click a bar for that night2035-03-29

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
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°
2035-03-06 Tue	21	—	unknown	19:50–20:35 (good, 0.75 h)	79.1° 15:00	9.42	10%	82.9°
2035-03-07 Wed	19	—	unknown	19:55–20:30 (good, 0.58 h)	79.1° 14:55	9.38	5%	71.3°
2035-03-08 Thu	18	—	unknown	19:55–20:25 (good, 0.5 h)	79.1° 14:55	9.33	1%	59.5°
2035-03-09 Fri	16	—	unknown	19:55–20:20 (good, 0.42 h)	79.1° 14:50	9.28	0%	47.8°
2035-03-10 Sat	14	—	unknown	19:55–20:15 (good, 0.33 h)	79.1° 14:45	9.23	1%	36.8°
2035-03-11 Sun	11	—	unknown	20:00–20:15 (good, 0.25 h)	79.1° 14:40	9.18	5%	27.7°
2035-03-12 Mon	9	—	unknown	20:00–20:05 (good, 0.08 h)	79.1° 14:35	9.13	11%	23.3°
2035-03-13 Tue	7	—	unknown	20:00–20:35 (marginal, 0.58 h)	79.1° 14:35	9.09	19%	26.4°
2035-03-14 Wed	5	—	unknown	20:00–20:30 (marginal, 0.5 h)	79.1° 14:30	9.04	29%	35.1°
2035-03-15 Thu	3	—	unknown	20:05–20:25 (marginal, 0.33 h)	79.1° 14:25	8.99	40%	46.4°
2035-03-16 Fri	2	—	unknown	20:05–20:20 (marginal, 0.25 h)	79.1° 14:20	8.94	51%	58.6°
2035-03-17 Sat	2	—	unknown	20:05–20:15 (marginal, 0.17 h)	79.1° 14:15	8.88	62%	71.3°
2035-03-18 Sun	2	—	unknown	20:05–20:10 (marginal, 0.08 h)	79.1° 14:15	8.83	73%	84.1°
2035-03-19 Mon	1	—	unknown	20:05–20:10 (marginal, 0.08 h)	79.1° 14:10	8.78	82%	96.8°
2035-03-20 Tue	1	—	unknown	—	79.1° 14:05	8.73	90%	109.4°
2035-03-21 Wed	1	—	unknown	—	79.1° 14:00	8.68	96%	121.5°
2035-03-22 Thu	1	—	unknown	—	79.1° 14:00	8.63	99%	133.1°
2035-03-23 Fri	1	—	unknown	—	79.1° 13:55	8.58	100%	143.6°
2035-03-24 Sat	0	—	unknown	—	79.1° 13:50	8.52	99%	152.0°
2035-03-25 Sun	0	—	unknown	—	79.1° 14:45	8.47	96%	156.5°
2035-03-26 Mon	0	—	unknown	—	79.1° 14:40	8.42	91%	155.1°
2035-03-27 Tue	0	—	unknown	—	79.1° 14:40	8.36	85%	148.9°
2035-03-28 Wed	0	—	unknown	—	79.1° 14:35	8.31	77%	140.2°
2035-03-29 Thu	0	—	unknown	—	79.1° 14:30	8.26	69%	130.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-02-28&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.