As long as people have been on Earth, looking up at the night sky, constellations have been there. Ancient people began to see patterns of stars in the sky and gave them names and these have become the constellations.
Well, first it's POLARIS, the North Star, it's found in the constellation "The Little Bear" or Ursa Minor.
Hydra is found in the constellation called Phoenix
The Pleiades is found in the constellation Taurus, the Bull.
Canopus can be found the the constellation Carina
Stars, galaxies, nebulae ... a constellation is just a defined patch of sky, so anything you'd normally find in the sky might be found in a constellation.
All of them
Instanly
comets.
in a triple-star system in the northern constellation Cygnus, or the swam
The Butterfly Cluster can be found in the constellation of Scorpius.
The knowledge of the Aquarius constellation has been around since the 2nd century. It was first written about by Ptolemy, but who first discovered it is not known.
The star Regulus, or Alpha Leonis, can be found in the constellation of Leo. It is the brightest star in the constellation.