Nuclear fusion: lecture 9.2 A

Fusion in the Sun At extreme temperatures and pressures, Hydrogen fuses into He in the core of the sun. Elements up to Calcium are created, also by fusion

Hydrogen fusion

Nuclear fusion Light nuclei are joined together, or fused, to make heavier nuclei. In stars, H fuses into He + gamma radiation + energy Fusion is what causes stars to shine

Stars fuse elements from H to Fe

Heavier elements are created by fusion in Supernova explosions

Solar system origins Our solar system was probably made from the outer layers of a supernova. All the heavy elements found on earth were made in that explosion by fusion reactions Planetary nebula IC418

Star-gas-star cycle

Can fusion be an energy source on Earth? + uses Hydrogen, an abundant element. + the oceans could provide power for millions of years. - Fusion creates dangerous neutron radiation - Experiments in making fusion energy are just beginning to be successful

Fusion research 1 lb of Hydrogen could yield the energy of 16,000,000 lbs of coal Water would be the source for Hydrogen

Fusion reactor Magnets spin H plasma @100 million C, high pressure The H fuses into He, releasing radiation and heat The heat energy would be used to make electricity

Tokamak reactor, Princeton University In 1993, achieved temperatures 3 X those of the sun