SOLAR SYSTEM

Detailed explanation-1: -Stars are made up of very hot gases. These gases are mostly hydrogen and helium, which are the two lightest elements. Stars shine by the fusion of hydrogen and helium in their cores.

Detailed explanation-2: -Stars are huge celestial bodies made mostly of hydrogen and helium that produce light and heat from the churning nuclear forges inside their cores.

Detailed explanation-3: -Hydrogen and helium are found in all stars. Ninety percent of all atoms in the universe are hydrogen atoms and fusion reactions fuel stars, resulting in the formation of helium and higher atomic number elements. This is the case because of the Big Bang, when temperatures were so high that only energy could exist.

Detailed explanation-4: -Using powerful telescopes, scientists have made extensive spectroscopic surveys of distant stars and galaxies. The data indicates that hydrogen and helium make up nearly all of the nuclear matter in the universe. The most abundant element, hydrogen, accounts for 74% of the mass while helium contributes 25%.