What are the stars made of?
A star in the sky looks as small as a firefly and much smaller than the light from a match. But actually it is a nuclear furnace, so big that our biggest atomic bomb is nothing at all. But the star, like our bombs, is a raging explosion of seething gases. And gases, like all other substances, are made from atoms.
Compared with a blazing star, our wonderful world is a frozen lump. But both the star and the earth are made from about a hundred different types of atom, On earth, the temperature is so low chat atoms of iron, tin and other substances reach their frozen state and become solid. Water particles are cool enough to be in a liquid state. But the earth is warm enough to keep a blanket of air made from atoms in the gaseous state.
No star is cool enough for any of its atoms to form solids or even liquids. If we dropped an iron poker into the sun, it would melt and turn to gassy vapor in a moment. If we wrapped the st,n in a sheet of ice 12 feet thick, the ice would turn to gaseous water vapor in less than a minute. All stars, then, are made entirely from seething gases.
On the cool earth, hydrogen is one of the rarest of elements. But in a seething star, hydrogen is the most plentiful of all elements. In fact, hydrogen is the fuel which a star uses to keep its nuclear furnace going. And this hydrogen is exactly like the small traces of hydrogen we find here on the earth.
The star we know most about is our sun and it is an average sized star made of average star materials.
Most of it is hydrogen gas, but there are traces of ether elements, just like those we find on our solid world. In the gases of the sun there are traces of iron and carbon and more than no other elements we find on the earth.
A star, we are told, begins life as a cloud of hydrogen gas. The atoms of hydrogen are the simplest of all atoms, having jus 6 one proton in the nucleus and one orbiting electron. As the star grows older, some of these hydrogen atoms team up to form larger atoms of helium, and other elements. The older stars have had time to form a few metals. But all the elements present in a star are in gaseous form.
The astronomer can identify the elements in a star with the spectrum, the glimmering band of colors we see in a rainbow. As it burns, each element accents a certain color in the spectrum and all the elements in a star are blazing gases. The element helium was discovered in the spectrum of the sun before we knew that helium was also present on the earth.