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: 02-23 (71), 02-22 (69), 02-20 (67), 02-21 (67), 02-19 (66) — by astronomy; check the weather when the night is within four days.

2034-01-25astronomy score per night — click a bar for that night2034-02-23

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-01-25 Wed	36	—	unknown	04:40–06:05 (good, 1.42 h)	87.1° 10:35	10.97	34%	92.0°
2034-01-26 Thu	37	—	unknown	04:40–06:05 (good, 1.42 h)	87.1° 10:30	10.94	45%	99.7°
2034-01-27 Fri	38	—	unknown	04:35–06:05 (good, 1.5 h)	87.1° 10:30	10.91	57%	106.9°
2034-01-28 Sat	39	—	unknown	04:30–06:05 (good, 1.58 h)	87.1° 10:25	10.88	68%	113.3°
2034-01-29 Sun	40	—	unknown	04:25–06:00 (good, 1.58 h)	87.1° 10:20	10.85	78%	118.4°
2034-01-30 Mon	41	—	unknown	04:30–06:00 (good, 1.5 h)	87.1° 10:15	10.82	86%	121.8°
2034-01-31 Tue	41	—	unknown	04:30–06:00 (good, 1.5 h)	87.1° 10:15	10.79	93%	123.2°
2034-02-01 Wed	36	—	unknown	04:25–06:00 (good, 1.58 h)	87.1° 10:10	10.76	97%	122.6°
2034-02-02 Thu	36	—	unknown	04:25–06:00 (good, 1.58 h)	87.1° 10:05	10.72	100%	120.0°
2034-02-03 Fri	35	—	unknown	04:25–06:00 (good, 1.58 h)	87.1° 10:00	10.69	100%	115.8°
2034-02-04 Sat	33	—	unknown	04:25–05:55 (good, 1.5 h)	87.1° 09:55	10.65	98%	110.5°
2034-02-05 Sun	32	—	unknown	04:25–05:55 (good, 1.5 h)	87.1° 09:55	10.62	94%	104.5°
2034-02-06 Mon	30	—	unknown	04:25–05:55 (good, 1.5 h)	87.1° 09:50	10.58	88%	98.0°
2034-02-07 Tue	30	—	unknown	04:20–05:55 (good, 1.58 h)	87.1° 09:45	10.55	81%	91.5°
2034-02-08 Wed	31	—	unknown	04:15–05:55 (good, 1.67 h)	87.1° 09:40	10.51	73%	84.9°
2034-02-09 Thu	32	—	unknown	04:10–05:50 (good, 1.67 h)	87.1° 09:35	10.47	64%	78.6°
2034-02-10 Fri	35	—	unknown	04:00–05:50 (good, 1.83 h)	87.1° 09:35	10.44	55%	72.6°
2034-02-11 Sat	38	—	unknown	03:55–05:50 (good, 1.92 h)	87.1° 09:30	10.4	46%	67.2°
2034-02-12 Sun	43	—	unknown	03:45–05:50 (good, 2.08 h)	87.1° 09:25	10.36	36%	62.6°
2034-02-13 Mon	48	—	unknown	03:25–05:45 (good, 2.33 h)	87.1° 09:20	10.32	27%	59.1°
2034-02-14 Tue	54	—	unknown	03:25–05:45 (good, 2.33 h)	87.1° 09:20	10.28	18%	57.0°
2034-02-15 Wed	57	—	unknown	03:20–05:45 (good, 2.42 h)	87.1° 09:15	10.24	11%	56.8°
2034-02-16 Thu	62	—	unknown	03:15–05:45 (good, 2.5 h)	87.1° 09:10	10.2	5%	58.5°
2034-02-17 Fri	63	—	unknown	03:10–05:40 (good, 2.5 h)	87.1° 09:05	10.16	2%	62.2°
2034-02-18 Sat	65	—	unknown	03:10–05:40 (good, 2.5 h)	87.1° 09:00	10.12	0%	67.7°
2034-02-19 Sun	66	—	unknown	03:05–05:40 (good, 2.58 h)	87.1° 09:00	10.08	1%	74.4°
2034-02-20 Mon	67	—	unknown	03:00–05:40 (good, 2.67 h)	87.1° 08:55	10.04	5%	81.9°
2034-02-21 Tue	67	—	unknown	02:55–05:35 (good, 2.67 h)	87.1° 08:50	10.0	12%	89.9°
2034-02-22 Wed	69	—	unknown	02:50–05:35 (good, 2.75 h)	87.1° 08:45	9.95	20%	97.9°
2034-02-23 Thu	71	—	unknown	02:50–05:35 (good, 2.75 h)	87.1° 08:40	9.91	30%	105.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-01-25&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.