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 North America Nebula: 03-15 (39), 03-13 (38), 03-14 (38), 03-12 (37), 03-11 (35) — by astronomy; check the weather when the night is within four days.

2048-02-15astronomy score per night — click a bar for that night2048-03-15

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2048-02-15 Sat	15	—	unknown	05:20–05:45 (good, 0.42 h)	87.1° 11:35	10.26	4%	53.3°
2048-02-16 Sun	16	—	unknown	05:20–05:45 (good, 0.42 h)	87.2° 11:35	10.22	10%	55.7°
2048-02-17 Mon	18	—	unknown	05:15–05:45 (good, 0.5 h)	87.2° 11:30	10.18	16%	59.8°
2048-02-18 Tue	18	—	unknown	05:10–05:40 (good, 0.5 h)	87.2° 11:25	10.14	24%	65.2°
2048-02-19 Wed	19	—	unknown	05:05–05:40 (good, 0.58 h)	87.2° 11:20	10.1	33%	71.4°
2048-02-20 Thu	21	—	unknown	05:00–05:40 (good, 0.67 h)	87.1° 11:20	10.05	42%	78.1°
2048-02-21 Fri	20	—	unknown	05:00–05:35 (good, 0.58 h)	87.2° 11:15	10.01	51%	85.1°
2048-02-22 Sat	22	—	unknown	04:55–05:35 (good, 0.67 h)	87.2° 11:10	9.97	61%	92.2°
2048-02-23 Sun	23	—	unknown	04:50–05:35 (good, 0.75 h)	87.2° 11:05	9.93	70%	99.4°
2048-02-24 Mon	24	—	unknown	04:45–05:35 (good, 0.83 h)	87.2° 11:00	9.88	78%	106.4°
2048-02-25 Tue	23	—	unknown	04:55–05:30 (good, 0.58 h)	87.1° 11:00	9.84	86%	112.9°
2048-02-26 Wed	23	—	unknown	04:50–05:30 (good, 0.67 h)	87.2° 10:55	9.8	92%	118.8°
2048-02-27 Thu	22	—	unknown	04:45–05:30 (good, 0.75 h)	87.2° 10:50	9.75	97%	123.4°
2048-02-28 Fri	21	—	unknown	04:45–05:25 (good, 0.67 h)	87.2° 10:45	9.71	99%	126.4°
2048-02-29 Sat	22	—	unknown	04:40–05:25 (good, 0.75 h)	87.1° 10:40	9.66	100%	127.1°
2048-03-01 Sun	22	—	unknown	04:35–05:25 (good, 0.83 h)	87.2° 10:40	9.62	98%	125.3°
2048-03-02 Mon	22	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:35	9.57	93%	121.2°
2048-03-03 Tue	23	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:30	9.52	86%	115.2°
2048-03-04 Wed	23	—	unknown	04:30–05:20 (good, 0.83 h)	87.2° 10:25	9.48	77%	107.8°
2048-03-05 Thu	23	—	unknown	04:25–05:15 (good, 0.83 h)	87.1° 10:25	9.43	67%	99.7°
2048-03-06 Fri	23	—	unknown	04:20–05:15 (good, 0.92 h)	87.2° 10:20	9.38	56%	91.2°
2048-03-07 Sat	25	—	unknown	04:15–05:15 (good, 1.0 h)	87.2° 10:15	9.34	44%	82.7°
2048-03-08 Sun	27	—	unknown	04:05–05:10 (good, 1.08 h)	87.2° 10:10	9.29	34%	74.6°
2048-03-09 Mon	30	—	unknown	03:50–05:10 (good, 1.33 h)	87.2° 10:05	9.24	23%	67.2°
2048-03-10 Tue	33	—	unknown	03:50–05:10 (good, 1.33 h)	87.1° 10:05	9.19	15%	60.9°
2048-03-11 Wed	35	—	unknown	03:45–05:05 (good, 1.33 h)	87.2° 10:00	9.14	8%	56.2°
2048-03-12 Thu	37	—	unknown	03:40–05:05 (good, 1.42 h)	87.2° 09:55	9.09	3%	53.4°
2048-03-13 Fri	38	—	unknown	03:35–05:05 (good, 1.5 h)	87.2° 09:50	9.04	1%	53.0°
2048-03-14 Sat	38	—	unknown	03:30–05:00 (good, 1.5 h)	87.1° 09:45	8.99	0%	54.7°
2048-03-15 Sun	39	—	unknown	03:30–05:00 (good, 1.5 h)	87.2° 09:45	8.94	2%	58.3°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2048-02-15&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.