Why did Sirius become a dog?

1, Black Dog, as the image of Arnie maggs, suits him very well. Sirius was originally the name of a star, and people often call it the dog star. It has this nickname because this star is called the giant dog in its constellation. 2. The image of Black Dog and Ani maggs is not only suitable for Sirius Black in name, but also the opposite in many other aspects. Magic black dogs often haunt Europe and North America mysteriously. In Britain, people often see such animals, calling them black shacks, old shacks, Sharky dogs, Shojaei monsters and Shojaei dogs. Residents of Fordshire in central England gave them the name Sirius used: bigfoot.