HOW WE USE THE ELECTROMAGNETIC SPECTRUM

There are few frequencies of electromagnetic radiation we haven't exploited, though some have their dangers...

- RICH EDWARDS

Radio waves, microwaves, gamma rays... all of these waves are made of the same 'stuff' — oscillating electric and magnetic fields moving at the speed of light. But that doesn't mean they're all alike. The various types of electromagnetic waves have different properties that are determined by their wavelengths — these can vary from the size of galaxies to smaller than the nucleus of an atom. Depending on the wave, they can either carry vast quantities of information or enable us to take a peek inside the human body. They can help us treat cancer and can offer up clues about the origin of the universe. Others help make life on Earth possible, while some can kill us.

HARD X-RAYS

WAVELENGTH: 0.01 TO 0.1 NANOMETRES

Far more penetrating than longer wavelength 'soft' X-rays, so-called hard X-rays can easily pass through materials like clothing or skin. But it’s the fact that they're absorbed by substances like metal and bone that makes them particularly useful for medical imaging and airport scanners.

UVB

WAVELENGTH: 280 TO 315 NANOMETRES