Nebula

In the 1930s, the term nebula was often used to describe any diffused astronomical object, including galaxies beyond the Milky Way. For instance, The Urantia Book mentions the Andromeda nebula, which is now called the Andromeda galaxy. Nonetheless, nebulae are still recognized as star-forming regions. They begin as giant clouds of dust and gas (mostly hydrogen and helium) hundreds of light years in diameter (see Wikipedia).