What Is #42: Helium?

The last post in this series took a look at hydrogen, the element on the periodic table with the lowest mass and the most abundant element in the Universe. Today we take a look at helium, the element with the second-lowest mass and the second most abundant element in the Universe. So what is helium?

Bensaccount at English Wikipedia / Public domain

A helium atom, by definition, has two protons. It normally has two neutrons in the nucleus, unless it is an isotope with a different number of neutrons. If neutral in charge, there are two electrons orbiting the nucleus in an electron cloud.

Astronomically speaking, helium came into being just after the Big Bang, along with hydrogen, although not nearly in the same quantities. Helium makes up about 10% of the Universe by number and 25% by mass. Since a helium atom has more mass than a hydrogen atom, the percentage by mass is higher than by number.

In stars, hydrogen fuses into helium, releasing energy in the core of a star. This is how stars produce energy. Without this process, Earth would not receive the needed energy from the Sun to harbor life. Stars will then fuse helium into carbon in their cores. Well, not every star as the lowest mass stars will not have a high enough core temperature to do this.

Helium on Earth? Helium balloons of course! Helium balloons float because helium has a lower density than the surrounding air, so it rises. Helium is used in many other places, including scientific research, coolants, medical equipment, etc. Needless to say, helium is very important to our daily lives!