← single night · whole-night plan

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.

2038-08-31astronomy score per night — click a bar for that night2038-09-29
night ofastronomyweatheroverall best windowhighestdark hMoonMoon sep.
2038-08-31 Tue 0 — unknown — 50.1° 15:15 7.56 3% 6.7°
2038-09-01 Wed 0 — unknown — 50.1° 15:10 7.62 9% 7.9°
2038-09-02 Thu 0 — unknown — 50.1° 15:05 7.67 17% 22.6°
2038-09-03 Fri 0 — unknown — 50.1° 15:00 7.73 26% 37.1°
2038-09-04 Sat 0 — unknown — 50.1° 14:55 7.78 37% 51.5°
2038-09-05 Sun 0 — unknown — 50.1° 14:55 7.84 48% 65.6°
2038-09-06 Mon 0 — unknown — 50.1° 14:50 7.89 60% 79.5°
2038-09-07 Tue 0 — unknown — 50.1° 14:45 7.95 70% 93.1°
2038-09-08 Wed 0 — unknown — 50.1° 14:40 8.0 79% 106.4°
2038-09-09 Thu 0 — unknown — 50.1° 14:40 8.06 87% 119.6°
2038-09-10 Fri 0 — unknown — 50.1° 14:35 8.11 93% 132.5°
2038-09-11 Sat 0 — unknown — 50.1° 14:30 8.16 97% 145.2°
2038-09-12 Sun 0 — unknown — 50.1° 14:25 8.22 100% 157.7°
2038-09-13 Mon 0 — unknown — 50.1° 14:20 8.27 100% 170.1°
2038-09-14 Tue 0 — unknown — 50.1° 14:20 8.32 98% 177.7°
2038-09-15 Wed 0 — unknown — 50.1° 14:15 8.38 94% 165.7°
2038-09-16 Thu 0 — unknown — 50.1° 14:10 8.43 89% 153.8°
2038-09-17 Fri 0 — unknown — 50.1° 14:05 8.48 83% 142.0°
2038-09-18 Sat 0 — unknown — 50.1° 14:00 8.53 75% 130.2°
2038-09-19 Sun 0 — unknown — 50.1° 14:00 8.59 67% 118.3°
2038-09-20 Mon 0 — unknown — 50.1° 13:55 8.64 57% 106.3°
2038-09-21 Tue 0 — unknown — 50.1° 13:50 8.69 48% 94.1°
2038-09-22 Wed 0 — unknown — 50.1° 13:45 8.74 38% 81.7°
2038-09-23 Thu 0 — unknown — 50.1° 13:45 8.79 28% 68.8°
2038-09-24 Fri 0 — unknown — 50.1° 13:40 8.84 19% 55.5°
2038-09-25 Sat 0 — unknown — 50.1° 13:35 8.89 11% 41.8°
2038-09-26 Sun 0 — unknown — 50.1° 13:30 8.94 5% 27.6°
2038-09-27 Mon 0 — unknown — 50.1° 13:25 8.99 1% 13.0°
2038-09-28 Tue 0 — unknown — 50.1° 13:25 9.04 0% 1.9°
2038-09-29 Wed 0 — unknown — 50.1° 13:20 9.09 2% 16.9°

Download: CSV · JSON


💡 API
curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2038-08-31&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.