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 Vega: 03-14 (92), 03-13 (91), 03-15 (91), 03-12 (90), 03-16 (90) — by astronomy; check the weather when the night is within four days.

2046-02-18astronomy score per night — click a bar for that night2046-03-19

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-02-18 Sun	52	—	unknown	03:20–05:40 (good, 2.33 h)	87.1° 09:00	10.12	94%	116.0°
2046-02-19 Mon	50	—	unknown	03:20–05:40 (good, 2.33 h)	87.1° 09:00	10.08	98%	114.2°
2046-02-20 Tue	47	—	unknown	03:20–05:40 (good, 2.33 h)	87.1° 08:55	10.03	100%	110.6°
2046-02-21 Wed	44	—	unknown	03:20–05:35 (good, 2.25 h)	87.1° 08:50	9.99	98%	105.6°
2046-02-22 Thu	43	—	unknown	03:20–05:35 (good, 2.25 h)	87.1° 08:45	9.95	94%	99.7°
2046-02-23 Fri	42	—	unknown	03:15–05:35 (good, 2.33 h)	87.1° 08:40	9.91	87%	93.3°
2046-02-24 Sat	43	—	unknown	03:10–05:30 (good, 2.33 h)	87.1° 08:40	9.86	78%	86.9°
2046-02-25 Sun	45	—	unknown	03:05–05:30 (good, 2.42 h)	87.1° 08:35	9.82	68%	80.9°
2046-02-26 Mon	49	—	unknown	02:55–05:30 (good, 2.58 h)	87.1° 08:30	9.77	58%	75.5°
2046-02-27 Tue	55	—	unknown	02:45–05:30 (good, 2.75 h)	87.1° 08:25	9.73	47%	70.9°
2046-02-28 Wed	62	—	unknown	02:30–05:25 (good, 2.92 h)	87.1° 08:25	9.69	37%	67.4°
2046-03-01 Thu	68	—	unknown	02:25–05:25 (good, 3.0 h)	87.1° 08:20	9.64	28%	65.0°
2046-03-02 Fri	75	—	unknown	02:20–05:25 (good, 3.08 h)	87.1° 08:15	9.59	20%	63.9°
2046-03-03 Sat	79	—	unknown	02:15–05:20 (good, 3.08 h)	87.1° 08:10	9.55	12%	64.1°
2046-03-04 Sun	81	—	unknown	02:15–05:20 (good, 3.08 h)	87.1° 08:05	9.5	7%	65.4°
2046-03-05 Mon	83	—	unknown	02:10–05:20 (good, 3.17 h)	87.1° 08:05	9.45	3%	67.8°
2046-03-06 Tue	83	—	unknown	02:05–05:15 (good, 3.17 h)	87.1° 08:00	9.41	1%	71.2°
2046-03-07 Wed	84	—	unknown	02:00–05:15 (good, 3.25 h)	87.1° 07:55	9.36	0%	75.3°
2046-03-08 Thu	86	—	unknown	01:55–05:15 (good, 3.33 h)	87.1° 07:50	9.31	1%	80.0°
2046-03-09 Fri	87	—	unknown	01:55–05:10 (good, 3.25 h)	87.1° 07:45	9.26	4%	85.0°
2046-03-10 Sat	88	—	unknown	01:50–05:10 (good, 3.33 h)	87.1° 07:45	9.22	9%	90.3°
2046-03-11 Sun	89	—	unknown	01:45–05:10 (good, 3.42 h)	87.1° 07:40	9.17	15%	95.6°
2046-03-12 Mon	90	—	unknown	01:40–05:05 (good, 3.42 h)	87.1° 07:35	9.12	23%	100.8°
2046-03-13 Tue	91	—	unknown	01:35–05:05 (good, 3.5 h)	87.1° 07:30	9.07	32%	105.6°
2046-03-14 Wed	92	—	unknown	01:35–05:05 (good, 3.5 h)	87.1° 07:30	9.02	42%	109.9°
2046-03-15 Thu	91	—	unknown	01:35–05:00 (good, 3.42 h)	87.1° 07:25	8.97	52%	113.3°
2046-03-16 Fri	90	—	unknown	01:35–05:00 (good, 3.42 h)	87.1° 07:20	8.92	63%	115.5°
2046-03-17 Sat	89	—	unknown	01:30–04:55 (good, 3.42 h)	87.1° 07:15	8.87	74%	116.3°
2046-03-18 Sun	87	—	unknown	01:30–04:55 (good, 3.42 h)	87.1° 07:10	8.82	83%	115.3°
2046-03-19 Mon	76	—	unknown	01:30–04:55 (good, 3.42 h)	87.1° 07:10	8.77	91%	112.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-02-18&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.