Another important use for the gas is as an inert atmospheric shield.
Its density of 0.0017837 grams per cubic centimeter is greater than both oxygen and nitrogen so it forms a heavier than air inert blanket over atmospheric sensitive processes.
Isotopes are atoms with the same number of protons and electrons, but a different number of neutrons. These are the elements that we see around us and find in nature. Radioactivity is measured using a unit called the "curie". The curie measures how many atoms spontaneously decay each second.
There are three main types of radiation or radioactive decay depending on the isotope.
Argon (symbol Ar) has the atomic number 18 and an atomic weight of 0.93%.
Natural argon consists of three stable isotopes the most common being argon-40 (99.6003%).
These include X-rays, medicine, carbon dating, energy generation, and to kill germs.
Some of the atoms may decay right away, while others will not decay for many thousands more years.
The thing to remember about half-life is that it is a probability.
Martian atmosphere is richer in this element containing 1.6 % argon.
It is a noble gas, found in group 18, period 3 and the p-block of the periodic table.