Radioactivity, the process by which the nuclei (cores) of unstable atoms of an element emit radiation (particles of matter and rays of energy), and in so doing become atoms of other elements.
We live in a radioactive world, and we're not just talking about the times when a nuclear plant is melting down and scaring the heck out of us. How much do you know about the ABGs (or alphas, betas and gammas) of nuclear radiation? See more »
British authorities have found traces of polonium-210 in at least five buildings and three British Airways jets since Alexander Litvinenko fell ill. See more »