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: 01-30 (41), 01-31 (41), 01-29 (40), 01-28 (39), 01-27 (38) — by astronomy; check the weather when the night is within four days.

2034-01-07astronomy score per night — click a bar for that night2034-02-05

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-01-07 Sat	11	—	unknown	05:20–06:45 (marginal, 1.42 h)	87.1° 11:45	11.37	89%	114.1°
2034-01-08 Sun	11	—	unknown	06:05–06:10 (good, 0.08 h)	87.1° 11:45	11.36	82%	108.5°
2034-01-09 Mon	11	—	unknown	06:05–06:10 (good, 0.08 h)	87.1° 11:40	11.34	74%	102.4°
2034-01-10 Tue	12	—	unknown	06:00–06:10 (good, 0.17 h)	87.1° 11:35	11.32	65%	95.9°
2034-01-11 Wed	14	—	unknown	05:55–06:10 (good, 0.25 h)	87.1° 11:30	11.3	56%	89.4°
2034-01-12 Thu	15	—	unknown	05:50–06:10 (good, 0.33 h)	87.1° 11:25	11.29	46%	82.9°
2034-01-13 Fri	17	—	unknown	05:45–06:10 (good, 0.42 h)	87.1° 11:25	11.27	37%	76.7°
2034-01-14 Sat	18	—	unknown	05:35–06:10 (good, 0.58 h)	87.1° 11:20	11.24	28%	70.9°
2034-01-15 Sun	21	—	unknown	05:30–06:10 (good, 0.67 h)	87.1° 11:15	11.22	20%	65.6°
2034-01-16 Mon	23	—	unknown	05:20–06:10 (good, 0.83 h)	87.1° 11:10	11.2	13%	61.3°
2034-01-17 Tue	25	—	unknown	05:15–06:10 (good, 0.92 h)	87.1° 11:10	11.18	7%	58.2°
2034-01-18 Wed	27	—	unknown	05:10–06:10 (good, 1.0 h)	87.1° 11:05	11.16	3%	56.8°
2034-01-19 Thu	29	—	unknown	05:05–06:10 (good, 1.08 h)	87.1° 11:00	11.13	0%	57.3°
2034-01-20 Fri	30	—	unknown	05:00–06:10 (good, 1.17 h)	87.1° 10:55	11.11	0%	59.8°
2034-01-21 Sat	31	—	unknown	05:00–06:05 (good, 1.08 h)	87.1° 10:50	11.08	3%	64.1°
2034-01-22 Sun	32	—	unknown	04:55–06:05 (good, 1.17 h)	87.1° 10:50	11.05	8%	69.9°
2034-01-23 Mon	33	—	unknown	04:50–06:05 (good, 1.25 h)	87.1° 10:45	11.03	15%	76.8°
2034-01-24 Tue	34	—	unknown	04:45–06:05 (good, 1.33 h)	87.1° 10:40	11.0	24%	84.3°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-01-07&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.