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: 10-10 (100), 10-11 (100), 10-12 (100), 10-13 (100), 10-14 (100) — by astronomy; check the weather when the night is within four days.

2026-10-10astronomy score per night — click a bar for that night2026-11-08

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2026-10-10 Sat	100	97	97	20:25–00:40 (good, 4.25 h)	87.1° 18:40	9.6	0%	91.0°
2026-10-11 Sun	100	0	0	—	87.1° 18:40	9.64	2%	85.6°
2026-10-12 Mon	100	0	0	—	87.1° 18:35	9.69	6%	80.5°
2026-10-13 Tue	100	0	0	—	87.1° 18:30	9.73	11%	75.8°
2026-10-14 Wed	100	—	unknown	20:15–00:25 (good, 4.17 h)	87.1° 18:25	9.78	17%	71.8°
2026-10-15 Thu	99	—	unknown	20:15–00:20 (good, 4.08 h)	87.1° 18:20	9.82	25%	68.6°
2026-10-16 Fri	92	—	unknown	20:15–00:20 (good, 4.08 h)	87.1° 18:20	9.86	34%	66.4°
2026-10-17 Sat	81	—	unknown	20:10–00:15 (good, 4.08 h)	87.1° 18:15	9.91	43%	65.1°
2026-10-18 Sun	69	—	unknown	20:10–23:55 (good, 3.75 h)	87.1° 18:10	9.95	52%	65.0°
2026-10-19 Mon	60	—	unknown	20:10–23:40 (good, 3.5 h)	87.1° 18:05	9.99	62%	66.1°
2026-10-20 Tue	53	—	unknown	20:10–23:15 (good, 3.08 h)	87.1° 18:05	10.03	71%	68.3°
2026-10-21 Wed	48	—	unknown	20:05–22:15 (good, 2.17 h)	87.1° 18:00	10.08	80%	71.6°
2026-10-22 Thu	44	—	unknown	20:05–21:40 (good, 1.58 h)	87.1° 17:55	10.12	87%	75.8°
2026-10-23 Fri	44	—	unknown	20:05–21:35 (good, 1.5 h)	87.1° 17:50	10.16	94%	80.9°
2026-10-24 Sat	47	—	unknown	20:00–21:50 (good, 1.83 h)	87.1° 17:45	10.2	98%	86.6°
2026-10-25 Sun	51	—	unknown	19:00–21:15 (good, 2.25 h)	87.1° 16:45	10.24	100%	92.6°
2026-10-26 Mon	58	—	unknown	19:00–21:50 (good, 2.83 h)	87.1° 16:40	10.28	99%	98.5°
2026-10-27 Tue	64	—	unknown	19:00–22:10 (good, 3.17 h)	87.1° 16:35	10.31	96%	104.1°
2026-10-28 Wed	72	—	unknown	18:55–22:10 (good, 3.25 h)	87.1° 16:30	10.35	90%	108.9°
2026-10-29 Thu	85	—	unknown	18:55–22:15 (good, 3.33 h)	87.1° 16:25	10.39	81%	112.5°
2026-10-30 Fri	88	—	unknown	18:55–22:15 (good, 3.33 h)	87.1° 16:25	10.43	71%	114.6°
2026-10-31 Sat	89	—	unknown	18:55–22:15 (good, 3.33 h)	87.1° 16:20	10.47	60%	115.1°
2026-11-01 Sun	89	—	unknown	18:50–22:15 (good, 3.42 h)	87.1° 16:15	10.5	49%	114.0°
2026-11-02 Mon	87	—	unknown	18:50–22:10 (good, 3.33 h)	87.1° 16:10	10.54	38%	111.4°
2026-11-03 Tue	86	—	unknown	18:50–22:05 (good, 3.25 h)	87.1° 16:05	10.57	28%	107.7°
2026-11-04 Wed	84	—	unknown	18:50–22:05 (good, 3.25 h)	87.1° 16:05	10.61	19%	103.1°
2026-11-05 Thu	82	—	unknown	18:50–22:00 (good, 3.17 h)	87.1° 16:00	10.64	12%	98.0°
2026-11-06 Fri	82	—	unknown	18:45–21:55 (good, 3.17 h)	87.1° 15:55	10.68	6%	92.6°
2026-11-07 Sat	80	—	unknown	18:45–21:50 (good, 3.08 h)	87.1° 15:50	10.71	2%	87.2°
2026-11-08 Sun	78	—	unknown	18:45–21:45 (good, 3.0 h)	87.1° 15:50	10.74	0%	82.0°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2026-10-10&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.