The white square is called the "search target marker", and marks on the map the location of the object which has most recently been searched for.

那个白方框叫做“搜索对象标记”，它在星图上标出最近搜索的天体的位置。

youdao

Taylor got away from his marker to meet Gretar Steinsson's cross but failed to find the target from inside the six-yard area.

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Auroras scientists use a fluorescent marker to tell them whether a candidate drug molecule has had an effect on the target molecule.

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