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: 02-17 (46), 02-18 (38), 02-19 (30), 03-02 (26), 02-29 (25) — by astronomy; check the weather when the night is within four days.

2048-02-17astronomy score per night — click a bar for that night2048-03-17

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2048-02-17 Mon	46	—	unknown	19:30–21:35 (good, 2.08 h)	79.2° 16:10	10.18	16%	21.9°
2048-02-18 Tue	38	—	unknown	19:35–21:25 (good, 1.83 h)	79.2° 16:05	10.14	24%	15.4°
2048-02-19 Wed	30	—	unknown	19:35–21:15 (good, 1.67 h)	79.2° 16:00	10.1	33%	16.9°
2048-02-20 Thu	24	—	unknown	19:35–20:20 (good, 0.75 h)	79.2° 15:55	10.05	42%	24.7°
2048-02-21 Fri	19	—	unknown	19:35–21:45 (marginal, 2.17 h)	79.2° 15:55	10.01	51%	34.8°
2048-02-22 Sat	15	—	unknown	19:40–21:40 (marginal, 2.0 h)	79.2° 15:50	9.97	61%	45.6°
2048-02-23 Sun	14	—	unknown	19:40–21:30 (marginal, 1.83 h)	79.2° 15:45	9.93	70%	56.9°
2048-02-24 Mon	14	—	unknown	19:40–21:30 (marginal, 1.83 h)	79.2° 15:40	9.88	78%	68.5°
2048-02-25 Tue	16	—	unknown	19:40–21:30 (marginal, 1.83 h)	79.2° 15:35	9.84	86%	80.5°
2048-02-26 Wed	18	—	unknown	19:40–20:00 (good, 0.33 h)	79.2° 15:35	9.8	92%	92.7°
2048-02-27 Thu	21	—	unknown	19:45–20:40 (good, 0.92 h)	79.2° 15:30	9.75	97%	105.3°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2048-02-17&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.