The vast expanse between galaxies isn't truly empty. Filling this space is the intergalactic medium, a hot, tenuous gas thought to be mostly hydrogen. But how much other material lurks there, and what temperatures does it reach? Astronomers believe this mysterious medium, possibly existing in a web-like structure, holds clues to the missing baryon problem - the vast amount of normal matter unaccounted for in the universe. Is the warm-hot intergalactic medium, a theorized component of this space,