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: 11-02 (90), 11-17 (77), 11-18 (77), 11-19 (77), 11-16 (76) — by astronomy; check the weather when the night is within four days.

2046-11-02astronomy score per night — click a bar for that night2046-12-01

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2046-11-02 Fri	90	—	unknown	18:50–22:40 (good, 3.83 h)	71.1° 17:35	10.54	25%	50.9°
2046-11-03 Sat	75	—	unknown	18:50–22:40 (good, 3.83 h)	71.1° 17:30	10.58	34%	44.9°
2046-11-04 Sun	61	—	unknown	18:50–22:20 (good, 3.5 h)	71.1° 17:30	10.61	44%	41.6°
2046-11-05 Mon	49	—	unknown	18:50–22:05 (good, 3.25 h)	71.1° 17:25	10.65	54%	41.3°
2046-11-06 Tue	41	—	unknown	18:45–20:15 (good, 1.5 h)	71.1° 17:20	10.68	63%	43.9°
2046-11-07 Wed	35	—	unknown	18:45–19:05 (good, 0.33 h)	71.1° 17:15	10.72	72%	48.8°
2046-11-08 Thu	31	—	unknown	18:45–22:30 (marginal, 3.75 h)	71.1° 17:10	10.75	80%	55.3°
2046-11-09 Fri	31	—	unknown	18:45–22:25 (marginal, 3.67 h)	71.1° 17:10	10.78	87%	62.9°
2046-11-10 Sat	33	—	unknown	18:45–19:10 (good, 0.42 h)	71.1° 17:05	10.81	93%	71.2°
2046-11-11 Sun	37	—	unknown	18:45–19:40 (good, 0.92 h)	71.1° 17:00	10.84	97%	79.9°
2046-11-12 Mon	44	—	unknown	18:40–20:25 (good, 1.75 h)	71.1° 16:55	10.87	99%	89.0°
2046-11-13 Tue	51	—	unknown	18:40–21:10 (good, 2.5 h)	71.1° 16:50	10.91	100%	98.2°
2046-11-14 Wed	59	—	unknown	18:40–21:35 (good, 2.92 h)	71.1° 16:50	10.93	98%	107.3°
2046-11-15 Thu	67	—	unknown	18:40–21:35 (good, 2.92 h)	71.1° 16:45	10.96	95%	116.2°
2046-11-16 Fri	76	—	unknown	18:40–21:35 (good, 2.92 h)	71.1° 16:40	10.99	90%	124.4°
2046-11-17 Sat	77	—	unknown	18:40–21:35 (good, 2.92 h)	71.1° 16:35	11.02	83%	131.5°
2046-11-18 Sun	77	—	unknown	18:40–21:35 (good, 2.92 h)	71.1° 16:35	11.05	74%	136.7°
2046-11-19 Mon	77	—	unknown	18:35–21:35 (good, 3.0 h)	71.1° 16:30	11.07	64%	139.0°
2046-11-20 Tue	76	—	unknown	18:35–21:30 (good, 2.92 h)	71.1° 16:25	11.1	54%	137.8°
2046-11-21 Wed	74	—	unknown	18:35–21:25 (good, 2.83 h)	71.1° 16:20	11.12	43%	133.1°
2046-11-22 Thu	73	—	unknown	18:35–21:25 (good, 2.83 h)	71.1° 16:15	11.15	32%	125.7°
2046-11-23 Fri	71	—	unknown	18:35–21:20 (good, 2.75 h)	71.1° 16:15	11.17	21%	116.4°
2046-11-24 Sat	70	—	unknown	18:35–21:15 (good, 2.67 h)	71.1° 16:10	11.19	12%	106.0°
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°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2046-11-02&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.