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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: 04-14 (58), 04-17 (58), 04-13 (57), 04-15 (57), 04-16 (57) — by astronomy; check the weather when the night is within four days.
2035-03-19astronomy score per night — click a bar for that night2035-04-17
night ofastronomyweatheroverall best windowhighestdark hMoonMoon sep.
2035-03-19 Mon 34 — unknown 03:40–04:55 (good, 1.25 h) 71.1° 08:35 8.78 82% 140.9°
2035-03-20 Tue 32 — unknown 03:35–04:55 (good, 1.33 h) 71.1° 08:30 8.73 90% 137.7°
2035-03-21 Wed 31 — unknown 03:35–04:50 (good, 1.25 h) 71.1° 08:25 8.68 96% 131.6°
2035-03-22 Thu 31 — unknown 03:30–04:50 (good, 1.33 h) 71.1° 08:20 8.63 99% 123.5°
2035-03-23 Fri 28 — unknown 03:30–04:45 (good, 1.25 h) 71.1° 08:15 8.58 100% 114.4°
2035-03-24 Sat 26 — unknown 04:35–05:45 (good, 1.17 h) 71.1° 09:15 8.52 99% 104.8°
2035-03-25 Sun 23 — unknown 04:40–05:45 (good, 1.08 h) 71.1° 09:10 8.47 96% 95.1°
2035-03-26 Mon 21 — unknown 05:05–05:40 (good, 0.58 h) 71.1° 09:05 8.42 91% 85.5°
2035-03-27 Tue 20 — unknown 05:20–05:40 (good, 0.33 h) 71.1° 09:00 8.36 85% 76.2°
2035-03-28 Wed 20 — unknown 05:20–05:40 (good, 0.33 h) 71.1° 08:55 8.31 77% 67.2°
2035-03-29 Thu 21 — unknown 05:05–05:35 (good, 0.5 h) 71.1° 08:55 8.26 69% 58.8°
2035-03-30 Fri 24 — unknown 04:25–05:35 (good, 1.17 h) 71.1° 08:50 8.2 60% 51.3°
2035-03-31 Sat 27 — unknown 04:05–05:30 (good, 1.42 h) 71.1° 08:45 8.15 50% 45.0°
2035-04-01 Sun 31 — unknown 03:55–05:30 (good, 1.58 h) 71.1° 08:40 8.09 41% 40.7°
2035-04-02 Mon 39 — unknown 03:35–05:30 (good, 1.92 h) 71.1° 08:40 8.04 31% 39.0°
2035-04-03 Tue 44 — unknown 03:35–05:25 (good, 1.83 h) 71.1° 08:35 7.98 22% 40.6°
2035-04-04 Wed 49 — unknown 03:30–05:25 (good, 1.92 h) 71.1° 08:30 7.93 14% 45.2°
2035-04-05 Thu 49 — unknown 03:25–05:20 (good, 1.92 h) 71.1° 08:25 7.87 8% 52.4°
2035-04-06 Fri 50 — unknown 03:20–05:20 (good, 2.0 h) 71.1° 08:20 7.82 3% 61.3°
2035-04-07 Sat 52 — unknown 03:15–05:20 (good, 2.08 h) 71.1° 08:20 7.76 0% 71.5°
2035-04-08 Sun 52 — unknown 03:15–05:15 (good, 2.0 h) 71.1° 08:15 7.7 0% 82.4°
2035-04-09 Mon 54 — unknown 03:10–05:15 (good, 2.08 h) 71.1° 08:10 7.65 3% 93.7°
2035-04-10 Tue 53 — unknown 03:05–05:10 (good, 2.08 h) 71.1° 08:05 7.59 8% 104.9°
2035-04-11 Wed 55 — unknown 03:00–05:10 (good, 2.17 h) 71.1° 08:00 7.53 16% 115.7°
2035-04-12 Thu 56 — unknown 02:55–05:10 (good, 2.25 h) 71.1° 08:00 7.48 26% 125.6°
2035-04-13 Fri 57 — unknown 02:55–05:05 (good, 2.17 h) 71.1° 07:55 7.42 37% 133.7°
2035-04-14 Sat 58 — unknown 02:50–05:05 (good, 2.25 h) 71.1° 07:50 7.36 48% 139.2°
2035-04-15 Sun 57 — unknown 02:50–05:00 (good, 2.17 h) 71.1° 07:45 7.3 59% 140.9°
2035-04-16 Mon 57 — unknown 02:45–05:00 (good, 2.25 h) 71.1° 07:45 7.25 70% 138.7°
2035-04-17 Tue 58 — unknown 02:45–05:00 (good, 2.25 h) 71.1° 07:40 7.19 79% 133.3°

Download: CSV · JSON


💡 API
curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2035-03-19&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.