You may be thinking, "But I thought Samus always had her power armor on," and you'd be mostly correct.
Being on the Super Nintendo Entertainment System, this game boasted the best graphics so far, and therefore the most well-drawn Samus thus far.
It seems back when she was younger, Samus had a really, really horrible hairstyle.
Even though the game was in black and white, programmers by this time were paying more attention to artists, and creating more detailed sprites and whatnot.
Certainly not in video games! Hardcore Metroid fans should be pleased to know that Samus does have her little mole under her lip.