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: 01-20 (30), 01-19 (28), 01-18 (27), 01-17 (25), 01-15 (24) — by astronomy; check the weather when the night is within four days.

2047-12-22astronomy score per night — click a bar for that night2048-01-20

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-12-22 Sun	11	—	unknown	18:35–18:40 (good, 0.08 h)	87.1° 12:55	11.51	39%	72.8°
2047-12-23 Mon	9	—	unknown	18:40–19:25 (marginal, 0.75 h)	87.1° 12:50	11.51	48%	78.3°
2047-12-24 Tue	8	—	unknown	18:40–19:20 (marginal, 0.67 h)	87.1° 12:50	11.5	58%	84.1°
2047-12-25 Wed	7	—	unknown	18:40–19:15 (marginal, 0.58 h)	87.1° 12:45	11.5	68%	89.9°
2047-12-26 Thu	7	—	unknown	18:40–19:10 (marginal, 0.5 h)	87.1° 12:40	11.5	76%	95.8°
2047-12-27 Fri	7	—	unknown	18:40–19:05 (marginal, 0.42 h)	87.1° 12:35	11.49	84%	101.4°
2047-12-28 Sat	7	—	unknown	18:40–19:05 (marginal, 0.42 h)	87.1° 12:30	11.49	90%	106.6°
2047-12-29 Sun	7	—	unknown	18:40–19:00 (marginal, 0.33 h)	87.1° 12:30	11.48	95%	111.2°
2047-12-30 Mon	6	—	unknown	05:55–06:10 (marginal, 0.25 h)	87.1° 12:25	11.47	98%	115.0°
2047-12-31 Tue	7	—	unknown	05:50–06:10 (marginal, 0.33 h)	87.1° 12:20	11.46	100%	117.8°
2048-01-01 Wed	7	—	unknown	05:45–06:10 (marginal, 0.42 h)	87.1° 12:15	11.45	100%	119.3°
2048-01-02 Thu	8	—	unknown	05:45–06:10 (marginal, 0.42 h)	87.1° 12:15	11.44	97%	119.3°
2048-01-03 Fri	8	—	unknown	05:40–06:10 (marginal, 0.5 h)	87.1° 12:10	11.43	93%	117.7°
2048-01-04 Sat	9	—	unknown	05:35–06:10 (marginal, 0.58 h)	87.1° 12:05	11.42	87%	114.7°
2048-01-05 Sun	9	—	unknown	05:30–06:10 (marginal, 0.67 h)	87.1° 12:00	11.41	79%	110.4°
2048-01-06 Mon	10	—	unknown	05:25–06:10 (marginal, 0.75 h)	87.1° 11:55	11.39	70%	105.0°
2048-01-07 Tue	10	—	unknown	05:25–06:45 (marginal, 1.33 h)	87.1° 11:50	11.38	59%	98.9°
2048-01-08 Wed	11	—	unknown	06:05–06:10 (good, 0.08 h)	87.1° 11:45	11.36	48%	92.2°
2048-01-09 Thu	13	—	unknown	06:00–06:10 (good, 0.17 h)	87.1° 11:40	11.35	37%	85.3°
2048-01-10 Fri	15	—	unknown	05:50–06:10 (good, 0.33 h)	87.1° 11:35	11.33	26%	78.5°
2048-01-11 Sat	18	—	unknown	05:45–06:10 (good, 0.42 h)	87.1° 11:35	11.31	17%	72.2°
2048-01-12 Sun	19	—	unknown	05:35–06:10 (good, 0.58 h)	87.1° 11:30	11.29	9%	66.8°
2048-01-13 Mon	21	—	unknown	05:30–06:10 (good, 0.67 h)	87.1° 11:25	11.27	3%	62.9°
2048-01-14 Tue	23	—	unknown	05:25–06:10 (good, 0.75 h)	87.1° 11:20	11.25	0%	60.8°
2048-01-15 Wed	24	—	unknown	05:25–06:10 (good, 0.75 h)	87.1° 11:20	11.23	0%	60.8°
2048-01-16 Thu	24	—	unknown	05:20–06:10 (good, 0.83 h)	87.1° 11:15	11.21	3%	62.7°
2048-01-17 Fri	25	—	unknown	05:15–06:10 (good, 0.92 h)	87.1° 11:10	11.19	8%	66.2°
2048-01-18 Sat	27	—	unknown	05:10–06:10 (good, 1.0 h)	87.1° 11:05	11.16	14%	70.9°
2048-01-19 Sun	28	—	unknown	05:10–06:10 (good, 1.0 h)	87.1° 11:00	11.14	22%	76.3°
2048-01-20 Mon	30	—	unknown	05:05–06:10 (good, 1.08 h)	87.1° 11:00	11.12	31%	82.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-12-22&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.