Isotopes are atoms that have the same number of protons and electrons, but a different number of neutrons. Changing the number of neutrons in an atom does not change the element. Atoms of elements with different numbers of neutrons are called "isotopes" of that element. There are 254 known stable isotopes and 80 elements which have at least one stable isotope.

Isotope 254

Rhincodon typus is a cosmopolitan tropical and warm temperate species and is the world's largest living chondrichthyan. Its life history is poorly understood, but it is known to be highly fecund and to migrate extremely large distances. Populations appear to have been depleted by harpoon fisheries in Southeast Asia and perhaps incidental capture in other fisheries. High value in international trade, a K-selected life history, highly migratory nature and normally low abundance make this species vulnerable to commercial fishing. Dive tourism involving this species has recently developed in a number of locations around the world, demonstrating that it is far more valuable alive than fished.

Rhincodon Typus

Alpha particles (symbol α ) are a type of ionizing radiation ejected by the nuclei of some unstable atoms. They are large subatomic fragments consisting of two protons and two neutrons.

α2+

Remix of track taken from Danny Deepo's "Sounds from a Living Planet" available for digital download on Bandcamp https://dannydeepo.bandcamp.com/album/sounds-from-a-living-planet

The Marsden Experiment