Earth-chan is an anime-style anthropomorphic character representing the planet Earth, characterized by her blue and green hair and frequent insistence that she is not flat. The concept originated on Twitter in late 2017 following a joke about making an anime where the planets are high school girls. Earth-chan quickly became a viral sensation, serving as both a mascot for environmental awareness and a playful rebuttal to the Flat Earth theory. The meme typically depicts her as a shy or defensive schoolgirl, often seen wearing a NASA t-shirt, and is widely used to promote recycling or simply to enjoy the 'moe' aesthetic applied to celestial bodies.