← 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.

Best nights for Great Orion Nebula: 03-14 (40), 03-15 (39), 03-16 (38), 03-17 (36), 03-13 (34) — by astronomy; check the weather when the night is within four days.
2036-03-08astronomy score per night — click a bar for that night2036-04-06
night ofastronomyweatheroverall best windowhighestdark hMoonMoon sep.
2036-03-08 Sat 11 — unknown 19:55–22:00 (marginal, 2.08 h) 42.9° 18:50 9.29 84% 45.7°
2036-03-09 Sun 13 — unknown 19:55–22:00 (marginal, 2.08 h) 42.9° 18:45 9.24 92% 58.2°
2036-03-10 Mon 17 — unknown 19:55–22:10 (marginal, 2.25 h) 42.9° 18:40 9.2 97% 71.4°
2036-03-11 Tue 22 — unknown 20:00–20:10 (good, 0.17 h) 42.9° 18:40 9.15 100% 84.7°
2036-03-12 Wed 28 — unknown 20:00–21:25 (good, 1.42 h) 42.9° 18:35 9.1 100% 97.9°
2036-03-13 Thu 34 — unknown 20:00–21:35 (good, 1.58 h) 42.9° 18:30 9.05 97% 110.7°
2036-03-14 Fri 40 — unknown 20:00–21:35 (good, 1.58 h) 42.9° 18:25 9.0 92% 123.0°
2036-03-15 Sat 39 — unknown 20:05–21:40 (good, 1.58 h) 42.9° 18:25 8.95 85% 134.3°
2036-03-16 Sun 38 — unknown 20:05–21:40 (good, 1.58 h) 42.9° 18:20 8.9 77% 144.4°
2036-03-17 Mon 36 — unknown 20:05–21:35 (good, 1.5 h) 42.9° 18:15 8.85 68% 152.1°
2036-03-18 Tue 34 — unknown 20:05–21:30 (good, 1.42 h) 42.9° 18:10 8.8 58% 155.9°
2036-03-19 Wed 32 — unknown 20:10–21:25 (good, 1.25 h) 42.9° 18:05 8.74 48% 154.2°
2036-03-20 Thu 31 — unknown 20:10–21:20 (good, 1.17 h) 42.9° 18:05 8.69 39% 148.1°
2036-03-21 Fri 29 — unknown 20:10–21:20 (good, 1.17 h) 42.9° 18:00 8.64 30% 139.7°
2036-03-22 Sat 28 — unknown 20:10–21:15 (good, 1.08 h) 42.9° 17:55 8.59 22% 130.0°
2036-03-23 Sun 26 — unknown 20:15–21:10 (good, 0.92 h) 42.9° 17:50 8.54 14% 119.7°
2036-03-24 Mon 24 — unknown 20:15–21:05 (good, 0.83 h) 42.9° 17:45 8.48 8% 108.9°
2036-03-25 Tue 23 — unknown 20:15–21:05 (good, 0.83 h) 42.9° 17:45 8.43 4% 97.7°
2036-03-26 Wed 22 — unknown 20:15–21:00 (good, 0.75 h) 42.9° 17:40 8.38 1% 86.3°
2036-03-27 Thu 19 — unknown 20:20–20:55 (good, 0.58 h) 42.9° 17:35 8.32 0% 74.7°
2036-03-28 Fri 17 — unknown 20:20–20:50 (good, 0.5 h) 42.9° 17:30 8.27 1% 63.0°
2036-03-29 Sat 16 — unknown 20:20–20:45 (good, 0.42 h) 42.9° 17:30 8.21 5% 51.4°
2036-03-30 Sun 12 — unknown 21:25–21:40 (good, 0.25 h) 42.9° 18:25 8.16 10% 40.4°
2036-03-31 Mon 10 — unknown 21:25–21:30 (good, 0.08 h) 42.9° 18:20 8.11 18% 30.9°
2036-04-01 Tue 7 — unknown 21:25–22:05 (marginal, 0.67 h) 42.9° 18:15 8.05 27% 24.8°
2036-04-02 Wed 5 — unknown 21:25–22:00 (marginal, 0.58 h) 42.9° 18:10 8.0 38% 25.3°
2036-04-03 Thu 3 — unknown 21:30–21:50 (marginal, 0.33 h) 42.9° 18:10 7.94 49% 32.1°
2036-04-04 Fri 2 — unknown 21:30–21:40 (marginal, 0.17 h) 42.9° 18:05 7.88 61% 42.4°
2036-04-05 Sat 2 — unknown — 42.9° 18:00 7.83 72% 54.3°
2036-04-06 Sun 2 — unknown — 42.9° 17:55 7.77 81% 66.9°

Download: CSV · JSON


💡 API
curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2036-03-08&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.