Most planet-formation models predict a “planet desert” within one astronomical unit (or the average distance from the Earth to the sun) of a host star.
大多数行星形成模型预言在主恒星一个天文单位（或从地球到太阳的平均距离）以内会有一个“沙漠之星”。
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That's key to understanding planetformation.
这是理解行星形成的关键。
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The standard theory of planetformation holds that no planet that large could be formed so close to a star, leading to the suggestion that the body is a companion star.