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CMB偶极子:加速穿越宇宙

(原标题: CMB Dipole: Speeding Through the Universe)

2022-04-03

浏览次数: 20

我们的地球并不是静止的。地球绕太阳转。太阳绕银河系中心运行。银河系在本星系群中绕轨道运行。本星系群落向室女座星系团。但这些速度小于所有这些物体相对于宇宙微波背景辐射(CMBR)的运动速度。在1993年COBE卫星拍摄的全天空地图中,地球运动方向的微波光呈现蓝移,因此温度更高,而天空另一侧的微波光呈现红移,温度更低。这张地图表明,相对于原始辐射,本星系群的移动速度约为每秒600公里。这种高速度最初是出乎意料的,其大小至今仍无法解释。为什么我们走得这么快?外面有什么?

查看原文解释

Our Earth is not at rest. The Earth moves around the Sun. The Sun orbits the center of the Milky Way Galaxy. The Milky Way Galaxy orbits in the Local Group of Galaxies. The Local Group falls toward the Virgo Cluster of Galaxies. But these speeds are less than the speed that all of these objects together move relative to the cosmic microwave background radiation (CMBR). In the featured all-sky map from the COBE satellite in 1993, microwave light in the Earth's direction of motion appears blueshifted and hence hotter, while microwave light on the opposite side of the sky is redshifted and colder. The map indicates that the Local Group moves at about 600 kilometers per second relative to this primordial radiation. This high speed was initially unexpected and its magnitude is still unexplained. Why are we moving so fast? What is out there?

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