Mobula rays are sometimes called flying rays, thanks to their acrobatic leaping. But scientists are not sure exactly why they do it. The rays have large, flat, diamond-shaped bodies and long fins, ...

German engineering firm Festo has created this flying manta ray. Dubbed the Air_ray, it’s a balloon made of an aluminum-vaporised “PET foil”. Inflated with helium, the Air_ray’s propulsion ...