: Stars have guided human navigation for millennia and continue to be a primary focus of astrophysical research at institutions like the Harvard & Smithsonian Center for Astrophysics . ZArchiver - Apps on Google Play
Stars begin their lives in massive clouds of dust and gas known as nebulas. Gravity pulls this material together until it becomes hot and dense enough for nuclear fusion to occur. stars.7z
: A star's fate is determined by its initial mass: : Stars have guided human navigation for millennia