The Big Bear Observatory is located in a clear mountain lake which is known for its atmospheric stability.

大熊天文台坐落于一个清澈的山湖中，那里以气流平稳闻名。

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The Big Bear Observatory is located in a clear mountain lake which is known for its atmospheric stability.

大熊天文台坐落于一个清澈的山湖中，那里以气流平稳闻名。

youdao