Description: 密度是物質或物體的一種物理特性，表示了其體積與質量的關係。密度越大，單位體積的質量就越大。物體的平均密度是其總質量除以總體積。在國際單位制（SI）下，其單位是千克/立方米（kg/m³）。

在太陽周圍的銀河系區域內，密度的數值可從星際氣體的約10^-20 kg/m³變化到中子星內部的超過10¹⁷ kg/m³。

地球上常見的密度數值介於這兩個極端之間，例如鐵的密度約為7800 kg/m³，水的密度約為1000 kg/m³，在海平面附近、圍繞著我們的空氣密度略高於1 kg/m³。

宇宙不僅包括恆星、行星和星系中的氣體，還包括星系之間和星系團之間相對空曠的空間。因此，宇宙中物質的平均密度約為10^-27 kg/m³。

Related Terms:

• Mass
• Neutron Star
• Interstellar Medium

Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher
The translation of this term and its definition is still awaiting approval

This is an automated transliteration of the simplified Chinese translation of this term

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