A tale of two galaxies——galaxy mergers and galaxy pairs

Galaxies are building blocks of the Universe. However, their distribution is not random. On a large scale, they have a net-like distribution, but on a small scale they form pairs,like our Milky Way and the Andromeda galaxy. Galaxy pairs finally merge into one system. Merging is one of the most important approaches for galaxies to assemble mass, and research on galaxy pairs can help us understand galaxy interaction and mass assembly. This paper focuses on the observation of galaxy pairs in modern astronomical surveys and the important role played by the data collected by the Guo Shou-Jing telescope (LAMOST) in the study of galaxy pairs.