Definition of thanksgiving for English Language Learners. Thanksgiving : the fourth Thursday in November in the U.S. or the second Monday in October in Canada celebrated as a legal holiday for people to be thankful for what they have.
A galaxy contains stars, gas and dust. In a spiral galaxy like the Milky Way, the stars, gas, and dust are organized into a bulge, a disk containing spiral arms, and a halo.. Elliptical galaxies have a bulge-like central region and a halo, but do not have a disk.
New rocket findings might change definition of galaxies. Galaxies might not have such discreet boundaries as we imagined. Instead, they might stretch out to great distances, forming a vast, interconnected sea of stars. We think stars are being scattered out into space during galaxy collisions.