Valerie Lorraine, aged 9, of Asbestos, Quebec for her question:
What are the stars made of?
The best time to see the stars is on a clear winter's night. They twinkle like a host of yellow candles over the dark velvety sky, Summer stars, too, are bright and beautiful. But it so happens that north of the equator, the brightest stars shine for us in the winter months.
How big would you guess they are, those brightest stars? Are they just yellow candles? No‑ because we know that they are trillions and trillions of miles away from us. They must be big and they must be blazing. Actually, almost any of them could swallow our whole world a million times and still have room to spare.
Fires, as we know, tend to burn themselves out. Why then do not the stars burn out. There are old records that show they have changed very little in thousands of years. So they cannot be ordinary bonfires. If they were they would have burned out long ago. We are told that if a fair sized star were made of coal it would burn to ashes in a few thousand years.
So what are they made of and what keeps them burning?‑ Let's take a look at the star nearest to us. It is the big golden fellow that smiles on us throughout the day. For millions of years, we are told, it has been pouring its steady heat upon the earth. It is our sun, whose golden rays are needed by every plant and living creature upon earth.
Our sun is made of blazing gases. Its heat is hard for us to imagine. We are some 93,005,000 miles away from it. Yet we can feel its fiery furnace across all that distance. The flaming gases on its surface reach temperatures of 6,000 degrees Centigrade. Its fiery center is far, far hotter. This is no ordinary bonfire, it is an atomic furnace. It blazes like a hydrogen bomb. Our H‑bomb goes off! in a split second. The sun's atomic furnace blazes steadily through the ages.
A11 the stars are made of such blazing gases. All of them atomic furnaces. However, they are not all exactly alike. Some are larger, far far larger than our sun, Some are not much bigger than the earth
Some are far hotter than the sun. Some are much cooler. Some are made of stuff that is much heavier than lead. Some are made of stuff lighter than thistledown.
The smaller stars tend to be the hot an3 heavy ones. The giant stars seem to be loosely packed. Their gases spread out over wide areas. Having more room, they tend to be cooler. They are only red hot. Smaller stars like our sun, are heavier and gold and yellow with heat. The small and heavy stars are closely packed and white hot.
When iron is heated, it melts and then turns to gas. So do gold, lead and most other substances. These are some of the gases that are present in the stars. In fact, stars are made of the different substances that make up the world, except they are so hot that they have turned to gases.