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: 02-22 (69), 02-24 (69), 02-23 (68), 02-25 (68), 02-21 (67) — by astronomy; check the weather when the night is within four days.

2048-01-28astronomy score per night — click a bar for that night2048-02-26

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2048-01-28 Tue	33	—	unknown	04:45–06:05 (good, 1.33 h)	87.1° 10:25	10.89	96%	119.0°
2048-01-29 Wed	32	—	unknown	04:40–06:00 (good, 1.33 h)	87.1° 10:25	10.86	99%	119.5°
2048-01-30 Thu	32	—	unknown	04:40–06:00 (good, 1.33 h)	87.1° 10:20	10.83	100%	118.3°
2048-01-31 Fri	31	—	unknown	04:35–06:00 (good, 1.42 h)	87.1° 10:15	10.8	99%	115.6°
2048-02-01 Sat	30	—	unknown	04:35–06:00 (good, 1.42 h)	87.1° 10:10	10.77	96%	111.5°
2048-02-02 Sun	30	—	unknown	04:35–06:00 (good, 1.42 h)	87.1° 10:05	10.74	90%	106.3°
2048-02-03 Mon	30	—	unknown	04:30–06:00 (good, 1.5 h)	87.1° 10:05	10.7	83%	100.2°
2048-02-04 Tue	30	—	unknown	04:30–05:55 (good, 1.42 h)	87.1° 10:00	10.67	74%	93.6°
2048-02-05 Wed	31	—	unknown	04:20–05:55 (good, 1.58 h)	87.1° 09:55	10.63	63%	86.7°
2048-02-06 Thu	34	—	unknown	04:15–05:55 (good, 1.67 h)	87.1° 09:50	10.6	52%	80.0°
2048-02-07 Fri	38	—	unknown	04:05–05:55 (good, 1.83 h)	87.1° 09:45	10.56	41%	73.7°
2048-02-08 Sat	43	—	unknown	03:55–05:55 (good, 2.0 h)	87.1° 09:45	10.53	30%	68.2°
2048-02-09 Sun	47	—	unknown	03:45–05:50 (good, 2.08 h)	87.1° 09:40	10.49	20%	63.9°
2048-02-10 Mon	52	—	unknown	03:40–05:50 (good, 2.17 h)	87.1° 09:35	10.45	12%	61.2°
2048-02-11 Tue	55	—	unknown	03:35–05:50 (good, 2.25 h)	87.1° 09:30	10.41	5%	60.5°
2048-02-12 Wed	57	—	unknown	03:35–05:50 (good, 2.25 h)	87.1° 09:25	10.38	2%	61.7°
2048-02-13 Thu	59	—	unknown	03:30–05:50 (good, 2.33 h)	87.1° 09:25	10.34	0%	64.6°
2048-02-14 Fri	58	—	unknown	03:25–05:45 (good, 2.33 h)	87.1° 09:20	10.3	1%	68.9°
2048-02-15 Sat	60	—	unknown	03:20–05:45 (good, 2.42 h)	87.1° 09:15	10.26	4%	74.2°
2048-02-16 Sun	62	—	unknown	03:15–05:45 (good, 2.5 h)	87.1° 09:10	10.22	10%	80.0°
2048-02-17 Mon	63	—	unknown	03:15–05:45 (good, 2.5 h)	87.1° 09:10	10.18	16%	86.0°
2048-02-18 Tue	63	—	unknown	03:10–05:40 (good, 2.5 h)	87.1° 09:05	10.14	24%	92.1°
2048-02-19 Wed	64	—	unknown	03:05–05:40 (good, 2.58 h)	87.1° 09:00	10.1	33%	98.0°
2048-02-20 Thu	66	—	unknown	03:00–05:40 (good, 2.67 h)	87.1° 08:55	10.05	42%	103.5°
2048-02-21 Fri	67	—	unknown	03:00–05:35 (good, 2.58 h)	87.1° 08:50	10.01	51%	108.5°
2048-02-22 Sat	69	—	unknown	02:55–05:35 (good, 2.67 h)	87.1° 08:50	9.97	61%	112.9°
2048-02-23 Sun	68	—	unknown	02:55–05:35 (good, 2.67 h)	87.1° 08:45	9.93	70%	116.3°
2048-02-24 Mon	69	—	unknown	02:55–05:35 (good, 2.67 h)	87.1° 08:40	9.88	78%	118.6°
2048-02-25 Tue	68	—	unknown	02:50–05:30 (good, 2.67 h)	87.1° 08:35	9.84	86%	119.6°
2048-02-26 Wed	67	—	unknown	02:50–05:30 (good, 2.67 h)	87.1° 08:30	9.8	92%	119.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2048-01-28&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.