Labels:text | paper | font | black and white | document OCR: NUCLEOSYNTHESIS is the process by which stars produce progressively more complex chemical elements. These elements are eventually released into space, where they combine to form the matter that makes up everything in the Universe - including ourselves. The rate at which this occurs, and the elements produced, depend on the mass of the star. LOW-MASS STARS All stars begin the process of nucleosynthesis by fusing hydrogen to form helium in their cores. Hydrogen is the simplest and most abundant element in existence. When a star of less than about 10 solar masses has a core made almost entirely of helium, the core contracts. As it contracts, the core heats up and ignites a shell of hydrogen surrounding the core. While hydrogen in this shell fuses to form helium, the core becomes hot enough to ...
