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: 03-16 (39), 03-17 (39), 03-14 (38), 03-15 (38), 03-18 (38) — by astronomy; check the weather when the night is within four days.

2046-02-17astronomy score per night — click a bar for that night2046-03-18

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-02-17 Sat	16	—	unknown	05:25–05:40 (good, 0.25 h)	87.1° 11:25	10.16	87%	107.0°
2046-02-18 Sun	15	—	unknown	05:20–05:40 (good, 0.33 h)	87.2° 11:25	10.12	94%	114.1°
2046-02-19 Mon	16	—	unknown	05:15–05:40 (good, 0.42 h)	87.2° 11:20	10.08	98%	120.0°
2046-02-20 Tue	17	—	unknown	05:15–05:40 (good, 0.42 h)	87.2° 11:15	10.03	100%	123.8°
2046-02-21 Wed	17	—	unknown	05:10–05:35 (good, 0.42 h)	87.2° 11:10	9.99	98%	125.1°
2046-02-22 Thu	18	—	unknown	05:05–05:35 (good, 0.5 h)	87.2° 11:10	9.95	94%	123.5°
2046-02-23 Fri	18	—	unknown	05:00–05:35 (good, 0.58 h)	87.2° 11:05	9.91	87%	119.6°
2046-02-24 Sat	18	—	unknown	05:00–05:30 (good, 0.5 h)	87.2° 11:00	9.86	78%	113.8°
2046-02-25 Sun	19	—	unknown	04:55–05:30 (good, 0.58 h)	87.2° 10:55	9.82	68%	107.0°
2046-02-26 Mon	20	—	unknown	04:50–05:30 (good, 0.67 h)	87.2° 10:50	9.77	58%	99.7°
2046-02-27 Tue	21	—	unknown	04:45–05:30 (good, 0.75 h)	87.2° 10:50	9.73	47%	92.2°
2046-02-28 Wed	22	—	unknown	04:40–05:25 (good, 0.75 h)	87.2° 10:45	9.69	37%	84.9°
2046-03-01 Thu	24	—	unknown	04:30–05:25 (good, 0.92 h)	87.2° 10:40	9.64	28%	77.9°
2046-03-02 Fri	27	—	unknown	04:20–05:25 (good, 1.08 h)	87.2° 10:35	9.59	20%	71.4°
2046-03-03 Sat	29	—	unknown	04:15–05:20 (good, 1.08 h)	87.1° 10:30	9.55	12%	65.7°
2046-03-04 Sun	29	—	unknown	04:15–05:20 (good, 1.08 h)	87.2° 10:30	9.5	7%	60.9°
2046-03-05 Mon	31	—	unknown	04:10–05:20 (good, 1.17 h)	87.2° 10:25	9.45	3%	57.4°
2046-03-06 Tue	31	—	unknown	04:05–05:15 (good, 1.17 h)	87.2° 10:20	9.41	1%	55.4°
2046-03-07 Wed	32	—	unknown	04:00–05:15 (good, 1.25 h)	87.2° 10:15	9.36	0%	55.0°
2046-03-08 Thu	34	—	unknown	03:55–05:15 (good, 1.33 h)	87.2° 10:15	9.31	1%	56.3°
2046-03-09 Fri	33	—	unknown	03:55–05:10 (good, 1.25 h)	87.2° 10:10	9.26	4%	59.2°
2046-03-10 Sat	34	—	unknown	03:50–05:10 (good, 1.33 h)	87.2° 10:05	9.22	9%	63.5°
2046-03-11 Sun	36	—	unknown	03:45–05:10 (good, 1.42 h)	87.2° 10:00	9.17	15%	68.9°
2046-03-12 Mon	36	—	unknown	03:40–05:05 (good, 1.42 h)	87.2° 09:55	9.12	23%	75.1°
2046-03-13 Tue	36	—	unknown	03:40–05:05 (good, 1.42 h)	87.2° 09:55	9.07	32%	82.0°
2046-03-14 Wed	38	—	unknown	03:35–05:05 (good, 1.5 h)	87.2° 09:50	9.02	42%	89.3°
2046-03-15 Thu	38	—	unknown	03:30–05:00 (good, 1.5 h)	87.2° 09:45	8.97	52%	96.8°
2046-03-16 Fri	39	—	unknown	03:25–05:00 (good, 1.58 h)	87.2° 09:40	8.92	63%	104.3°
2046-03-17 Sat	39	—	unknown	03:30–04:55 (good, 1.42 h)	87.1° 09:35	8.87	74%	111.4°
2046-03-18 Sun	38	—	unknown	03:30–04:55 (good, 1.42 h)	87.2° 09:35	8.82	83%	117.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-02-17&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.