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: 01-25 (36), 01-26 (36), 01-23 (34), 01-24 (34), 01-27 (33) — by astronomy; check the weather when the night is within four days.

2029-01-04astronomy score per night — click a bar for that night2029-02-02

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2029-01-04 Thu	9	—	unknown	05:30–06:10 (marginal, 0.67 h)	87.1° 12:00	11.41	78%	109.9°
2029-01-05 Fri	9	—	unknown	05:30–06:10 (marginal, 0.67 h)	87.1° 11:55	11.4	68%	104.2°
2029-01-06 Sat	10	—	unknown	05:25–06:45 (marginal, 1.33 h)	87.1° 11:50	11.38	57%	97.8°
2029-01-07 Sun	11	—	unknown	06:05–06:10 (good, 0.08 h)	87.1° 11:45	11.37	46%	91.1°
2029-01-08 Mon	13	—	unknown	06:00–06:10 (good, 0.17 h)	87.1° 11:40	11.35	35%	84.3°
2029-01-09 Tue	15	—	unknown	05:50–06:10 (good, 0.33 h)	87.1° 11:40	11.34	24%	77.9°
2029-01-10 Wed	17	—	unknown	05:45–06:10 (good, 0.42 h)	87.1° 11:35	11.32	16%	72.1°
2029-01-11 Thu	19	—	unknown	05:35–06:10 (good, 0.58 h)	87.1° 11:30	11.3	8%	67.3°
2029-01-12 Fri	21	—	unknown	05:30–06:10 (good, 0.67 h)	87.1° 11:25	11.28	4%	63.8°
2029-01-13 Sat	23	—	unknown	05:30–06:10 (good, 0.67 h)	87.1° 11:20	11.26	1%	61.7°
2029-01-14 Sun	23	—	unknown	05:25–06:10 (good, 0.75 h)	87.1° 11:20	11.24	0%	61.2°
2029-01-15 Mon	24	—	unknown	05:20–06:10 (good, 0.83 h)	87.1° 11:15	11.22	2%	62.3°
2029-01-16 Tue	26	—	unknown	05:15–06:10 (good, 0.92 h)	87.1° 11:10	11.2	5%	64.7°
2029-01-17 Wed	27	—	unknown	05:10–06:10 (good, 1.0 h)	87.1° 11:05	11.17	10%	68.3°
2029-01-18 Thu	28	—	unknown	05:10–06:10 (good, 1.0 h)	87.1° 11:05	11.15	17%	72.8°
2029-01-19 Fri	29	—	unknown	05:05–06:10 (good, 1.08 h)	87.1° 11:00	11.13	24%	77.8°
2029-01-20 Sat	30	—	unknown	05:00–06:10 (good, 1.17 h)	87.1° 10:55	11.1	33%	83.3°
2029-01-21 Sun	31	—	unknown	04:55–06:05 (good, 1.17 h)	87.1° 10:50	11.08	42%	88.9°
2029-01-22 Mon	32	—	unknown	04:55–06:05 (good, 1.17 h)	87.1° 10:45	11.05	51%	94.6°
2029-01-23 Tue	34	—	unknown	04:50–06:05 (good, 1.25 h)	87.1° 10:45	11.02	61%	100.3°
2029-01-24 Wed	34	—	unknown	04:45–06:05 (good, 1.33 h)	87.1° 10:40	10.99	70%	105.7°
2029-01-25 Thu	36	—	unknown	04:40–06:05 (good, 1.42 h)	87.1° 10:35	10.96	79%	110.5°
2029-01-26 Fri	36	—	unknown	04:45–06:05 (good, 1.33 h)	87.1° 10:30	10.94	87%	114.6°
2029-01-27 Sat	33	—	unknown	04:45–06:05 (good, 1.33 h)	87.1° 10:25	10.91	93%	117.5°
2029-01-28 Sun	33	—	unknown	04:40–06:05 (good, 1.42 h)	87.1° 10:25	10.88	98%	118.8°
2029-01-29 Mon	32	—	unknown	04:40–06:00 (good, 1.33 h)	87.1° 10:20	10.84	100%	118.2°
2029-01-30 Tue	31	—	unknown	04:40–06:00 (good, 1.33 h)	87.1° 10:15	10.81	99%	115.7°
2029-01-31 Wed	31	—	unknown	04:35–06:00 (good, 1.42 h)	87.1° 10:10	10.78	96%	111.5°
2029-02-01 Thu	30	—	unknown	04:35–06:00 (good, 1.42 h)	87.1° 10:10	10.75	90%	105.9°
2029-02-02 Fri	29	—	unknown	04:35–06:00 (good, 1.42 h)	87.1° 10:05	10.71	82%	99.5°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2029-01-04&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.