They would have a real doomsday clock the counted down each shrinkage of the binary’s orbital period.

他们将真的会记录下双体的轨道周期每次缩短的时间，倒数着末日到来的日子。

The Doomsday Clock is a symbolic clockface that the Bulletin has maintained since 1947 at its headquarters on the campus of the University of Chicago.

末日时钟是1947年起在芝加哥大学校园公报总部立起的一个象徵性「钟面」。