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 HD 189733: 11-25 (68), 11-26 (65), 11-27 (63), 11-28 (62), 11-29 (60) — by astronomy; check the weather when the night is within four days.

2046-11-25astronomy score per night — click a bar for that night2046-12-24

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-11-25 Sun	68	—	unknown	18:35–21:10 (good, 2.58 h)	71.2° 16:05	11.22	6%	95.0°
2046-11-26 Mon	65	—	unknown	18:35–21:10 (good, 2.58 h)	71.1° 16:00	11.24	2%	83.9°
2046-11-27 Tue	63	—	unknown	18:35–21:05 (good, 2.5 h)	71.1° 15:55	11.26	0%	73.0°
2046-11-28 Wed	62	—	unknown	18:35–21:00 (good, 2.42 h)	71.1° 15:55	11.28	1%	62.9°
2046-11-29 Thu	60	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 15:50	11.3	5%	53.9°
2046-11-30 Fri	55	—	unknown	18:35–20:50 (good, 2.25 h)	71.1° 15:45	11.32	11%	46.8°
2046-12-01 Sat	49	—	unknown	18:35–20:50 (good, 2.25 h)	71.1° 15:40	11.33	19%	42.3°
2046-12-02 Sun	41	—	unknown	18:35–20:35 (good, 2.0 h)	71.1° 15:40	11.35	27%	40.9°
2046-12-03 Mon	34	—	unknown	18:35–20:25 (good, 1.83 h)	71.1° 15:35	11.37	36%	42.6°
2046-12-04 Tue	29	—	unknown	18:35–20:10 (good, 1.58 h)	71.2° 15:30	11.38	46%	46.9°
2046-12-05 Wed	24	—	unknown	18:35–19:15 (good, 0.67 h)	71.1° 15:25	11.4	56%	53.0°
2046-12-06 Thu	21	—	unknown	18:35–18:40 (good, 0.08 h)	71.1° 15:20	11.41	65%	60.4°
2046-12-07 Fri	20	—	unknown	18:35–20:45 (marginal, 2.17 h)	71.1° 15:20	11.42	74%	68.5°
2046-12-08 Sat	20	—	unknown	18:35–20:40 (marginal, 2.08 h)	71.1° 15:15	11.43	81%	77.1°
2046-12-09 Sun	20	—	unknown	18:35–18:50 (good, 0.25 h)	71.2° 15:10	11.44	88%	86.1°
2046-12-10 Mon	22	—	unknown	18:35–19:20 (good, 0.75 h)	71.1° 15:05	11.45	94%	95.3°
2046-12-11 Tue	25	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 15:00	11.46	98%	104.6°
2046-12-12 Wed	28	—	unknown	18:35–19:50 (good, 1.25 h)	71.1° 15:00	11.47	100%	113.7°
2046-12-13 Thu	30	—	unknown	18:35–19:50 (good, 1.25 h)	71.1° 14:55	11.48	100%	122.3°
2046-12-14 Fri	30	—	unknown	18:35–19:45 (good, 1.17 h)	71.2° 14:50	11.49	98%	129.9°
2046-12-15 Sat	33	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 14:45	11.49	93%	135.8°
2046-12-16 Sun	32	—	unknown	18:35–19:50 (good, 1.25 h)	71.1° 14:40	11.5	87%	138.9°
2046-12-17 Mon	31	—	unknown	18:35–19:45 (good, 1.17 h)	71.1° 14:40	11.5	78%	138.5°
2046-12-18 Tue	30	—	unknown	18:35–19:40 (good, 1.08 h)	71.2° 14:35	11.5	69%	134.5°
2046-12-19 Wed	29	—	unknown	18:35–19:35 (good, 1.0 h)	71.1° 14:30	11.51	58%	127.7°
2046-12-20 Thu	27	—	unknown	18:35–19:35 (good, 1.0 h)	71.1° 14:25	11.51	46%	119.0°
2046-12-21 Fri	25	—	unknown	18:35–19:30 (good, 0.92 h)	71.1° 14:25	11.51	35%	109.1°
2046-12-22 Sat	24	—	unknown	18:35–19:25 (good, 0.83 h)	71.1° 14:20	11.51	25%	98.6°
2046-12-23 Sun	22	—	unknown	18:40–19:20 (good, 0.67 h)	71.2° 14:15	11.51	15%	87.7°
2046-12-24 Mon	20	—	unknown	18:40–19:15 (good, 0.58 h)	71.1° 14:10	11.5	8%	77.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-11-25&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.