Mars Express, an ESA mission, has found a unique crater on Mars shaped like a butterfly. This crater lies in the Idaeus Fossae region. It was made by a space rock hitting Mars at a low angle. This caused debris to fly out in two large lobes that look like butterfly wings. The crater is about 20 km wide and 15 km long, showing the impact was from a large object. What makes this crater special is some of the debris looks "fluidised" or smooth, like a mudslide. ESA scientists think the impact might have melted ice below the surface, allowing the material to flow. This suggests there may have been liquid water on Mars when the crater formed. Around the butterfly crater are volcanic mesas and wrinkle ridges. These features show Mars had volcanic activity in the past. The mesas are flat-topped and made from layers of lava and ash. Wrinkle ridges formed as lava cooled and shrank. These details help scientists learn how Mars’ surface changed over billions of years. ESA released this discovery on December 3, 2025. The butterfly crater helps scientists study how asteroid impacts and local features affect crater shapes. It also gives clues about Mars’ climate history and the role of water. Such findings improve our understanding of whether Mars could have once supported life.