Impossible: Physics beyond the Edge

On Sunshine and Invisible Particles (1x4)

Air date: Jan 01, 2010

Investigate two challenges to the law of conservation of energy, also known as the first law of thermodynamics. In the 19th century, the source of the sun's energy seemed inexplicable, until the discovery of radioactivity. Then, in the 20th century, a type of radioactive decay appeared to violate energy conservation, until the discovery of an invisible elementary particle.