What's the name of the largest constellation?

The longest constellation-Ophiuchus. Of the 88 constellations in the whole day, Ophiuchus is the longest and largest constellation, with Cancer on its head and Libra on its tail, spanning the sky 1/4. Ophiuchus is another monument of Hercules, a great hero in Greek mythology. According to legend, Ophiuchus is the incarnation of Xu Dela, the water snake spirit. This snake essence has nine heads and nine mouths, which is extremely harmful. If one of its heads is cut off, two heads will grow immediately, which will double the ferocity. After Hercules, the hero of the earth, destroyed the lion essence, he went with his nephew Olaus to find the water snake essence to kill people. In order to prevent the snake's head from multiplying, they adopted a wonderful method: whenever Hercules cut off a snake's head, Olaus immediately burned the wound on the snake's neck with fire, so that the snake's head could not grow.

With courage and wisdom, they finally eliminated the water snake essence. To commemorate the achievements of Hercules, Zeus lifted this water snake to the sky. Whenever people see this long snake, they will miss Hercules, the hero who fought bravely with the elite of water snakes. When observing Ophiuchus, we will also find that this "snake" seems to be carrying a heavy bowl on its back. This "bowl" is the grand duke. There is a crow (crow's nest) on the snake's tail. It is pecking constantly. Maybe its relatives were killed by a long snake venom and are now taking revenge. It is worth mentioning that Ophiuchus, although extremely long, does not have a dazzling star. There is only one second-class bright star that emits red light. (that is, alpha snake), the heart of Ophiuchus is Star One. Because there are no other bright stars around the stars, Arabs are vividly called "loners".