C27 Xinghe let's start with the cp(12)

"Actually, Sirius is a double star, and what humans can see with their naked eyes is the main star of Sirius, Sirius A. Because it was larger and brighter than Earth, even though Sirius was far away from Earth, it could be seen hundreds of thousands of light-years away. But Planet A's brother, Planet B, was not so lucky, because it was about the same mass as Earth