So-Jun was browsing through the shelves, looking for some particular subject books. Where is it? He said to himself. He continued to walk around the library. "Science, Science Fiction, Biology, Chemistry..." He said as he read the labels of the book shelves. "Where is the Astronomy one?" He asked himself. He already asked the librarian for astronomy books a while ago and she said that there's some astronomy books here, he just need to find it.