This study examines the impact of geographic distance on scientific collaboration, with a focus on the mobility of coauthors as a proxy for changes in distance. While advancements in information, communication, and transportation technologies have facilitated collaboration across distances, the extent to which these means of communication compensate for the lack of face-to-face interaction remains a subject of ongoing debate. By utilizing a matching method to construct two groups of scientist pairs and comparing the changes in their collaboration performance before and after mobility, the causal effect of geographic change on collaboration is estimated. The findings indicate that when collaborators who previously resided in the same city relocate to different cities, the productivity and citation impact of their co-publications are significantly reduced. These results suggest that physical proximity still plays a crucial role in scientific collaboration despite the availability of technological means for remote collaboration.