Today's Rocket Words: Your 5 words and meanings to learn
radioactive
a substance which emits radiation
gamma ray
electromagnetic radiation emitted by an atomic nucleus during radioactive decay
radiotherapy
treatment of disease using x-rays or other forms of radiation
alpha particle
a positively charged particle that consists of two protons and two neutrons emitted during radioactive decay
isotope
atoms of the same element that have a different mass number because they have a different number of neutrons