Hydrogen is the primary constituent of the sun's core. The fusion reaction continues in the sun and other stars because these high temperatures cause the hydrogen nuclei to vibrate. And the more they vibrate, the more likely they are to collide, fuse, and then create additional energy to sustain the process. A star can also explode, or supernova, if it produces more energy than is required to sustain the fusion reaction. Per reaction, fusion gives off much more energy than fission.
Fusion also avoids the dangerous radioactive waste associated with fission.
But scientists have yet to be able to reproduce the tremendous temperatures required for a fusion reaction. Due to the large volume of mail we receive only questions for publication can be answered. The official Web site of Popular Science Magazine. Terms and Conditions of Use.