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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 Triangulum Pinwheel: 03-04 (22), 03-05 (19), 03-06 (15), 03-07 (11), 03-08 (9) — by astronomy; check the weather when the night is within four days.
2041-03-04astronomy score per night — click a bar for that night2041-04-02
night ofastronomyweatheroverall best windowhighestdark hMoonMoon sep.
2041-03-04 Mon 22 — unknown 19:50–20:40 (good, 0.83 h) 79.2° 15:05 9.49 8% 27.5°
2041-03-05 Tue 19 — unknown 19:50–20:30 (good, 0.67 h) 79.2° 15:05 9.45 15% 21.0°
2041-03-06 Wed 15 — unknown 19:50–20:20 (good, 0.5 h) 79.2° 15:00 9.4 23% 22.4°
2041-03-07 Thu 11 — unknown 19:55–20:05 (good, 0.17 h) 79.2° 14:55 9.35 33% 30.2°
2041-03-08 Fri 9 — unknown 19:55–20:50 (marginal, 0.92 h) 79.2° 14:50 9.3 43% 40.3°
2041-03-09 Sat 7 — unknown 19:55–20:40 (marginal, 0.75 h) 79.2° 14:45 9.25 53% 51.1°
2041-03-10 Sun 6 — unknown 19:55–20:35 (marginal, 0.67 h) 79.2° 14:45 9.21 62% 62.2°
2041-03-11 Mon 5 — unknown 20:00–20:30 (marginal, 0.5 h) 79.2° 14:40 9.16 71% 73.3°
2041-03-12 Tue 4 — unknown 20:00–20:30 (marginal, 0.5 h) 79.2° 14:35 9.11 80% 84.4°
2041-03-13 Wed 4 — unknown 20:00–20:30 (marginal, 0.5 h) 79.2° 14:30 9.06 86% 95.4°
2041-03-14 Thu 4 — unknown 20:00–20:30 (marginal, 0.5 h) 79.2° 14:25 9.01 92% 106.5°
2041-03-15 Fri 4 — unknown 20:05–20:25 (marginal, 0.33 h) 79.2° 14:25 8.96 96% 117.5°
2041-03-16 Sat 3 — unknown 20:05–20:20 (marginal, 0.25 h) 79.2° 14:20 8.91 99% 128.3°
2041-03-17 Sun 3 — unknown 20:05–20:15 (marginal, 0.17 h) 79.2° 14:15 8.86 100% 138.9°
2041-03-18 Mon 3 — unknown 20:05–20:15 (marginal, 0.17 h) 79.2° 14:10 8.81 99% 148.7°
2041-03-19 Tue 2 — unknown 19:35–19:40 (marginal, 0.08 h) 79.2° 14:10 8.75 96% 156.5°
2041-03-20 Wed 1 — unknown — 79.2° 14:05 8.7 91% 159.6°
2041-03-21 Thu 1 — unknown — 79.2° 14:00 8.65 84% 155.7°
2041-03-22 Fri 1 — unknown — 79.2° 13:55 8.6 76% 147.0°
2041-03-23 Sat 1 — unknown — 79.2° 13:50 8.55 66% 136.1°
2041-03-24 Sun 0 — unknown — 79.2° 13:50 8.49 56% 124.1°
2041-03-25 Mon 0 — unknown — 79.2° 13:45 8.44 44% 111.4°
2041-03-26 Tue 0 — unknown — 79.2° 13:40 8.39 33% 98.3°
2041-03-27 Wed 0 — unknown — 79.2° 13:35 8.33 23% 84.8°
2041-03-28 Thu 0 — unknown — 79.2° 13:30 8.28 14% 71.1°
2041-03-29 Fri 0 — unknown — 79.2° 13:30 8.23 7% 57.4°
2041-03-30 Sat 0 — unknown — 79.2° 13:25 8.17 2% 44.2°
2041-03-31 Sun 0 — unknown — 79.2° 14:20 8.12 0% 32.1°
2041-04-01 Mon 0 — unknown — 79.2° 14:15 8.06 1% 23.0°
2041-04-02 Tue 0 — unknown — 79.2° 14:15 8.01 5% 20.6°

Download: CSV · JSON


💡 API
curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2041-03-04&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.