What's New?

Bad Astronomy

BA Blog
Q & BA
Bulletin Board

Bitesize Astronomy
Book Store
Bad Astro Store
Mad Science
Fun Stuff
Site Info

Search the site
Powered by Google

- Universe Today
- The Nine Planets
- Mystery Investigators
- Slacker Astronomy
- Skepticality

Buy My Stuff
Bad Astronomy at
Keep Bad Astronomy close to your heart, and help make me filthy rich. Hey, it's either this or one of those really irritating PayPal donation buttons here.


Posted by Bobby
Grade level: 4-6
School: Jefferson Elementy
City: Winston Salem State/Province: North Carolina
Country: United States
Area of science: Chemistry


How does the sun produce energy to burn? If we can duplicate this way of producing energy, can we have enough energy to last a long time? If my theorey isn't correct, please tell me when you send me the answer to my other question.

When we say the Sun "burns", that's really not what we mean. The Sun produces energy the same way a hydrogen bomb does!

Everything in the Universe that is solid, liquid or gas (like a rock, or a flower, or a glass of water) is made of tiny particles called atoms. There are different kinds of atoms. The lightest kind is called hydrogen, and it is the most common atom in the Universe. All the stars you can see when you look at them at night are almost completely made up of hydrogen.

Now, when you squeeze hydrogen VERY hard, a bunch of the atoms will stick together, and change they way they are put together. This is called atomic fusion. The fused atoms form the next heavier type of atom, which is helium (the same one that is used in balloons). It turns out that when they do this, they give off a little bit of energy. It's not much energy-- you'd never see it if it happened right in the palm of your hand-- but the Sun has lots of hydrogen. In the core of the Sun the pressure is high enough (and it's hot enough too) to make hydrogen turn into helium in huge amounts. There is so much hydrogen being converted to helium (hundred of millions of tons every second!) that a truly stupendous amount of energy is released. This is what causes the Sun to shine. That energy works its way out from the core of the Sun to the surface and then shines down on the Earth and all the other planets.

This is also the way a hydrogen bomb works, except that a bomb does its conversion of hydrogen to helium all at once, while the Sun does it nice and steadily over billions of years. The Sun cannot blow up like a bomb! Now, there are lots of scientists and engineers right here on Earth trying very hard to duplicate fusion the way the Sun does it, because it is a very good source of energy: it gives off lots of energy, and it is very clean. There are no radioactive materials given off like atomic fission does.

If you want to know more about the Sun, there is a wonderful web site called "The Nine Planets" that has lots of information about all the objects in the solar system.

©2008 Phil Plait. All Rights Reserved.

This page last modified


Q&A 1996

Q&A 1997

Q&A 1998

Q&A 1999

Q&A 2000

Subscribe to the Bad Astronomy Newsletter!

Talk about Bad Astronomy on the BA Bulletin Board!