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: 10-16 (100), 10-17 (100), 10-18 (100), 10-19 (95), 11-02 (86) — by astronomy; check the weather when the night is within four days.

2042-10-16astronomy score per night — click a bar for that night2042-11-14

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2042-10-16 Thu	100	—	unknown	20:15–00:20 (good, 4.08 h)	87.1° 18:20	9.87	7%	75.6°
2042-10-17 Fri	100	—	unknown	20:10–00:15 (good, 4.08 h)	87.1° 18:15	9.91	13%	72.2°
2042-10-18 Sat	100	—	unknown	20:10–00:10 (good, 4.0 h)	87.1° 18:10	9.95	20%	69.5°
2042-10-19 Sun	95	—	unknown	20:10–00:05 (good, 3.92 h)	87.1° 18:05	10.0	28%	67.7°
2042-10-20 Mon	84	—	unknown	20:05–00:00 (good, 3.92 h)	87.1° 18:05	10.04	38%	67.0°
2042-10-21 Tue	73	—	unknown	20:05–00:00 (good, 3.92 h)	87.1° 18:00	10.08	48%	67.5°
2042-10-22 Wed	63	—	unknown	20:05–23:35 (good, 3.5 h)	87.1° 17:55	10.12	58%	69.2°
2042-10-23 Thu	55	—	unknown	20:05–23:20 (good, 3.25 h)	87.1° 17:50	10.16	69%	72.1°
2042-10-24 Fri	51	—	unknown	20:00–22:35 (good, 2.58 h)	87.1° 17:45	10.2	79%	76.2°
2042-10-25 Sat	48	—	unknown	20:00–22:05 (good, 2.08 h)	87.1° 17:45	10.24	88%	81.2°
2042-10-26 Sun	48	—	unknown	19:00–21:00 (good, 2.0 h)	87.1° 16:40	10.28	94%	86.8°
2042-10-27 Mon	50	—	unknown	19:00–21:10 (good, 2.17 h)	87.1° 16:35	10.32	99%	92.7°
2042-10-28 Tue	56	—	unknown	18:55–21:40 (good, 2.75 h)	87.1° 16:30	10.36	100%	98.5°
2042-10-29 Wed	62	—	unknown	18:55–22:00 (good, 3.08 h)	87.1° 16:25	10.4	98%	103.8°
2042-10-30 Thu	68	—	unknown	18:55–22:00 (good, 3.08 h)	87.1° 16:25	10.43	93%	108.1°
2042-10-31 Fri	80	—	unknown	18:55–22:05 (good, 3.17 h)	87.1° 16:20	10.47	86%	111.1°
2042-11-01 Sat	84	—	unknown	18:50–22:05 (good, 3.25 h)	87.1° 16:15	10.51	78%	112.7°
2042-11-02 Sun	86	—	unknown	18:50–22:05 (good, 3.25 h)	87.1° 16:10	10.54	68%	112.9°
2042-11-03 Mon	86	—	unknown	18:50–22:05 (good, 3.25 h)	87.1° 16:10	10.58	58%	111.8°
2042-11-04 Tue	84	—	unknown	18:50–22:05 (good, 3.25 h)	87.1° 16:05	10.61	47%	109.6°
2042-11-05 Wed	82	—	unknown	18:50–22:00 (good, 3.17 h)	87.1° 16:00	10.65	38%	106.6°
2042-11-06 Thu	82	—	unknown	18:45–21:55 (good, 3.17 h)	87.1° 15:55	10.68	28%	102.8°
2042-11-07 Fri	80	—	unknown	18:45–21:50 (good, 3.08 h)	87.1° 15:50	10.71	20%	98.7°
2042-11-08 Sat	78	—	unknown	18:45–21:45 (good, 3.0 h)	87.1° 15:50	10.75	13%	94.2°
2042-11-09 Sun	77	—	unknown	18:45–21:45 (good, 3.0 h)	87.1° 15:45	10.78	8%	89.6°
2042-11-10 Mon	75	—	unknown	18:45–21:40 (good, 2.92 h)	87.1° 15:40	10.81	3%	85.0°
2042-11-11 Tue	73	—	unknown	18:45–21:35 (good, 2.83 h)	87.1° 15:35	10.84	1%	80.6°
2042-11-12 Wed	73	—	unknown	18:40–21:30 (good, 2.83 h)	87.1° 15:30	10.87	0%	76.5°
2042-11-13 Thu	71	—	unknown	18:40–21:30 (good, 2.83 h)	87.1° 15:30	10.9	1%	72.9°
2042-11-14 Fri	70	—	unknown	18:40–21:25 (good, 2.75 h)	87.1° 15:25	10.93	4%	70.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2042-10-16&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.