CARNET NEBULA

A Nebula is à interstellar cloud of dust, hydrogen, helium and other ionized gas . Originally, nebula was a name for any diffuse astronomical object, including galaxies beyond the Milky Way. Most nebulae are of vast size, even hundreds of light years in diameter. Although denser than the space surrounding them, most nebulae are far less dense than any vacuum created in an earthen environment - a nebular cloud the size of the Earth would have a total mesure of only a few kilograms.