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: 11-12 (88), 11-13 (85), 11-14 (79), 11-15 (72), 11-16 (62) — by astronomy; check the weather when the night is within four days.

2034-11-12astronomy score per night — click a bar for that night2034-12-11

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2034-11-12 Sun	88	—	unknown	18:40–22:00 (good, 3.33 h)	71.1° 16:55	10.87	3%	63.2°
2034-11-13 Mon	85	—	unknown	18:40–22:00 (good, 3.33 h)	71.1° 16:50	10.9	7%	55.1°
2034-11-14 Tue	79	—	unknown	18:40–21:55 (good, 3.25 h)	71.1° 16:50	10.93	13%	48.0°
2034-11-15 Wed	72	—	unknown	18:40–21:50 (good, 3.17 h)	71.1° 16:45	10.96	20%	42.4°
2034-11-16 Thu	62	—	unknown	18:40–21:45 (good, 3.08 h)	71.1° 16:40	10.99	28%	39.2°
2034-11-17 Fri	52	—	unknown	18:40–21:25 (good, 2.75 h)	71.1° 16:35	11.02	38%	38.9°
2034-11-18 Sat	43	—	unknown	18:40–21:15 (good, 2.58 h)	71.1° 16:30	11.04	47%	42.0°
2034-11-19 Sun	37	—	unknown	18:35–20:15 (good, 1.67 h)	71.1° 16:30	11.07	58%	47.9°
2034-11-20 Mon	32	—	unknown	18:35–19:20 (good, 0.75 h)	71.1° 16:25	11.1	68%	56.1°
2034-11-21 Tue	30	—	unknown	18:35–19:10 (good, 0.58 h)	71.1° 16:20	11.12	78%	65.7°
2034-11-22 Wed	32	—	unknown	18:35–19:20 (good, 0.75 h)	71.1° 16:15	11.15	87%	76.5°
2034-11-23 Thu	35	—	unknown	18:35–19:55 (good, 1.33 h)	71.1° 16:15	11.17	94%	88.0°
2034-11-24 Fri	41	—	unknown	18:35–20:40 (good, 2.08 h)	71.1° 16:10	11.19	98%	99.8°
2034-11-25 Sat	49	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 16:05	11.21	100%	111.4°
2034-11-26 Sun	54	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 16:00	11.24	98%	122.3°
2034-11-27 Mon	59	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 15:55	11.26	94%	131.6°
2034-11-28 Tue	60	—	unknown	18:35–20:50 (good, 2.25 h)	71.1° 15:55	11.28	87%	138.3°
2034-11-29 Wed	60	—	unknown	18:35–20:55 (good, 2.33 h)	71.1° 15:50	11.3	78%	141.2°
2034-11-30 Thu	58	—	unknown	18:35–20:50 (good, 2.25 h)	71.1° 15:45	11.31	68%	139.9°
2034-12-01 Fri	56	—	unknown	18:35–20:50 (good, 2.25 h)	71.1° 15:40	11.33	58%	135.1°
2034-12-02 Sat	54	—	unknown	18:35–20:45 (good, 2.17 h)	71.1° 15:35	11.35	48%	128.0°
2034-12-03 Sun	53	—	unknown	18:35–20:40 (good, 2.08 h)	71.1° 15:35	11.36	38%	119.8°
2034-12-04 Mon	52	—	unknown	18:35–20:35 (good, 2.0 h)	71.1° 15:30	11.38	28%	110.9°
2034-12-05 Tue	50	—	unknown	18:35–20:30 (good, 1.92 h)	71.1° 15:25	11.39	20%	101.7°
2034-12-06 Wed	48	—	unknown	18:35–20:30 (good, 1.92 h)	71.1° 15:20	11.41	13%	92.5°
2034-12-07 Thu	46	—	unknown	18:35–20:25 (good, 1.83 h)	71.1° 15:20	11.42	8%	83.2°
2034-12-08 Fri	44	—	unknown	18:35–20:20 (good, 1.75 h)	71.1° 15:15	11.43	3%	74.1°
2034-12-09 Sat	43	—	unknown	18:35–20:15 (good, 1.67 h)	71.1° 15:10	11.44	1%	65.3°
2034-12-10 Sun	42	—	unknown	18:35–20:10 (good, 1.58 h)	71.1° 15:05	11.45	0%	57.1°
2034-12-11 Mon	40	—	unknown	18:35–20:10 (good, 1.58 h)	71.1° 15:00	11.46	1%	49.7°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2034-11-12&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.