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: 12-04 (38), 12-05 (37), 12-06 (36), 12-07 (34), 12-08 (33) — by astronomy; check the weather when the night is within four days.

2045-12-04astronomy score per night — click a bar for that night2046-01-02

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2045-12-04 Mon	38	—	unknown	18:35–20:05 (good, 1.5 h)	87.1° 14:05	11.39	14%	88.0°
2045-12-05 Tue	37	—	unknown	18:35–20:00 (good, 1.42 h)	87.1° 14:00	11.4	8%	82.1°
2045-12-06 Wed	36	—	unknown	18:35–19:55 (good, 1.33 h)	87.1° 13:55	11.41	3%	76.6°
2045-12-07 Thu	34	—	unknown	18:35–19:50 (good, 1.25 h)	87.1° 13:55	11.43	0%	71.9°
2045-12-08 Fri	33	—	unknown	18:35–19:50 (good, 1.25 h)	87.1° 13:50	11.44	0%	68.1°
2045-12-09 Sat	31	—	unknown	18:35–19:45 (good, 1.17 h)	87.1° 13:45	11.45	2%	65.5°
2045-12-10 Sun	29	—	unknown	18:35–19:40 (good, 1.08 h)	87.1° 13:40	11.46	6%	64.1°
2045-12-11 Mon	27	—	unknown	18:35–19:35 (good, 1.0 h)	87.1° 13:35	11.47	12%	64.0°
2045-12-12 Tue	24	—	unknown	18:35–19:25 (good, 0.83 h)	87.1° 13:35	11.47	18%	65.2°
2045-12-13 Wed	21	—	unknown	18:35–19:20 (good, 0.75 h)	87.1° 13:30	11.48	26%	67.5°
2045-12-14 Thu	18	—	unknown	18:35–19:10 (good, 0.58 h)	87.1° 13:25	11.49	35%	70.8°
2045-12-15 Fri	16	—	unknown	18:35–19:00 (good, 0.42 h)	87.1° 13:20	11.49	44%	74.8°
2045-12-16 Sat	14	—	unknown	18:35–18:50 (good, 0.25 h)	87.1° 13:15	11.5	54%	79.4°
2045-12-17 Sun	13	—	unknown	18:35–18:45 (good, 0.17 h)	87.1° 13:15	11.5	63%	84.4°
2045-12-18 Mon	12	—	unknown	18:35–18:40 (good, 0.08 h)	87.1° 13:10	11.5	72%	89.8°
2045-12-19 Tue	11	—	unknown	18:00–19:35 (marginal, 1.58 h)	87.1° 13:05	11.51	81%	95.3°
2045-12-20 Wed	11	—	unknown	18:00–19:35 (marginal, 1.58 h)	87.1° 13:00	11.51	88%	100.8°
2045-12-21 Thu	10	—	unknown	18:05–19:30 (marginal, 1.42 h)	87.1° 13:00	11.51	94%	105.9°
2045-12-22 Fri	10	—	unknown	18:05–19:25 (marginal, 1.33 h)	87.1° 12:55	11.51	98%	110.4°
2045-12-23 Sat	9	—	unknown	18:40–19:20 (marginal, 0.67 h)	87.1° 12:50	11.5	100%	113.8°
2045-12-24 Sun	9	—	unknown	18:40–19:15 (marginal, 0.58 h)	87.1° 12:45	11.5	99%	115.8°
2045-12-25 Mon	10	—	unknown	18:05–19:15 (marginal, 1.17 h)	87.1° 12:40	11.5	95%	116.0°
2045-12-26 Tue	10	—	unknown	18:40–19:10 (marginal, 0.5 h)	87.1° 12:40	11.49	89%	114.4°
2045-12-27 Wed	9	—	unknown	18:40–19:05 (marginal, 0.42 h)	87.1° 12:35	11.49	80%	111.2°
2045-12-28 Thu	9	—	unknown	18:40–19:00 (marginal, 0.33 h)	87.1° 12:30	11.48	70%	106.7°
2045-12-29 Fri	8	—	unknown	18:40–18:55 (marginal, 0.25 h)	87.1° 12:25	11.48	59%	101.4°
2045-12-30 Sat	8	—	unknown	05:50–06:10 (marginal, 0.33 h)	87.1° 12:20	11.47	48%	95.5°
2045-12-31 Sun	7	—	unknown	05:50–06:10 (marginal, 0.33 h)	87.1° 12:20	11.46	37%	89.5°
2046-01-01 Mon	8	—	unknown	05:45–06:10 (marginal, 0.42 h)	87.1° 12:15	11.45	27%	83.6°
2046-01-02 Tue	9	—	unknown	05:40–06:10 (marginal, 0.5 h)	87.1° 12:10	11.44	18%	78.1°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2045-12-04&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.