There is no single astronomer who "found" the constellation Leo. Constellations are groups of stars that appear close to each other in the sky from our perspective on Earth.

Here's why there's no one discoverer:

* Ancient Origins: Constellations have been observed and named by people for thousands of years. Ancient civilizations like the Babylonians, Egyptians, and Greeks all recognized the pattern of stars we now call Leo.

* Cultural Variations: Different cultures often had their own names and stories associated with the same constellations.

* Formalization: The modern constellations we recognize today were formalized in the 19th century by the International Astronomical Union (IAU). This wasn't about discovering new constellations but rather establishing a standardized system for astronomers to use.

So, while we can't point to a single discoverer of Leo, the constellation has been a part of our understanding of the night sky for a very long time!