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分点

2027年 秋分

日付と時刻

UTC

概要

太陽が天の赤道を南へ横切る—北半球では秋の始まり。

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An equinox occurs when the Sun crosses the celestial equator (0° declination), giving roughly equal day and night globally. The March equinox marks spring in the Northern Hemisphere; the September equinox marks autumn. Equinox dates are ideal for calibrating solar declination and understanding Earth's axial tilt.

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データソース

至点・分点の日付はJPL DE440暦(NASAが使用する惑星・月暦と同じもの)から計算されています。流星群の極大日とZHR値は国際流星機構(IMO)の年次カレンダーに準拠しています。惑星イベントデータはNASA Horizonsシステムから取得しています。

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All tools on fastool.io run entirely in your browser — zero data leaves your device. No personal data is collected, stored, or transmitted to any server. Solar calculations use SunCalc.js; lunar data uses JPL DE440 ephemeris; coordinate transforms use publicly documented EPSG/OGC standards. This site requires no signup, no account, and no cloud processing.