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: 03-02 (26), 02-29 (25), 03-01 (25), 03-03 (25), 02-28 (24) — by astronomy; check the weather when the night is within four days.

2048-02-28astronomy score per night — click a bar for that night2048-03-28

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2048-02-28 Fri	24	—	unknown	19:45–20:45 (good, 1.0 h)	79.2° 15:25	9.71	99%	118.1°
2048-02-29 Sat	25	—	unknown	19:45–20:45 (good, 1.0 h)	79.2° 15:20	9.66	100%	131.0°
2048-03-01 Sun	25	—	unknown	19:45–20:40 (good, 0.92 h)	79.2° 15:20	9.62	98%	143.9°
2048-03-02 Mon	26	—	unknown	19:50–20:45 (good, 0.92 h)	79.2° 15:15	9.57	93%	155.9°
2048-03-03 Tue	25	—	unknown	19:50–20:40 (good, 0.83 h)	79.2° 15:10	9.52	86%	164.3°
2048-03-04 Wed	23	—	unknown	19:50–20:40 (good, 0.83 h)	79.2° 15:05	9.48	77%	162.4°
2048-03-05 Thu	22	—	unknown	19:50–20:35 (good, 0.75 h)	79.2° 15:00	9.43	67%	152.3°
2048-03-06 Fri	20	—	unknown	19:55–20:30 (good, 0.58 h)	79.2° 15:00	9.38	56%	139.8°
2048-03-07 Sat	18	—	unknown	19:55–20:25 (good, 0.5 h)	79.2° 14:55	9.34	44%	126.6°
2048-03-08 Sun	16	—	unknown	19:55–20:25 (good, 0.5 h)	79.2° 14:50	9.29	34%	113.3°
2048-03-09 Mon	14	—	unknown	19:55–20:20 (good, 0.42 h)	79.2° 14:45	9.24	23%	99.9°
2048-03-10 Tue	12	—	unknown	20:00–20:15 (good, 0.25 h)	79.2° 14:40	9.19	15%	86.6°
2048-03-11 Wed	11	—	unknown	20:00–20:10 (good, 0.17 h)	79.2° 14:40	9.14	8%	73.6°
2048-03-12 Thu	9	—	unknown	20:00–20:05 (good, 0.08 h)	79.2° 14:35	9.09	3%	60.7°
2048-03-13 Fri	8	—	unknown	20:00–20:05 (good, 0.08 h)	79.2° 14:30	9.04	1%	48.2°
2048-03-14 Sat	7	—	unknown	19:30–20:30 (marginal, 1.0 h)	79.2° 14:25	8.99	0%	36.3°
2048-03-15 Sun	5	—	unknown	20:05–20:25 (marginal, 0.33 h)	79.2° 14:20	8.94	2%	25.5°
2048-03-16 Mon	4	—	unknown	20:05–20:20 (marginal, 0.25 h)	79.2° 14:20	8.89	6%	17.1°
2048-03-17 Tue	3	—	unknown	20:05–20:15 (marginal, 0.17 h)	79.2° 14:15	8.84	11%	15.5°
2048-03-18 Wed	2	—	unknown	20:05–20:10 (marginal, 0.08 h)	79.2° 14:10	8.79	18%	21.8°
2048-03-19 Thu	1	—	unknown	—	79.2° 14:05	8.74	25%	31.4°
2048-03-20 Fri	1	—	unknown	—	79.2° 14:05	8.69	34%	42.0°
2048-03-21 Sat	0	—	unknown	—	79.2° 14:00	8.64	43%	53.1°
2048-03-22 Sun	0	—	unknown	—	79.2° 13:55	8.58	52%	64.4°
2048-03-23 Mon	0	—	unknown	—	79.2° 13:50	8.53	62%	76.1°
2048-03-24 Tue	0	—	unknown	—	79.2° 13:45	8.48	71%	88.0°
2048-03-25 Wed	0	—	unknown	—	79.2° 13:45	8.42	80%	100.3°
2048-03-26 Thu	0	—	unknown	—	79.2° 13:40	8.37	88%	112.9°
2048-03-27 Fri	0	—	unknown	—	79.2° 13:35	8.32	94%	125.7°
2048-03-28 Sat	0	—	unknown	—	79.2° 13:30	8.26	98%	138.8°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2048-02-28&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.