When a particle of a given type encounters a corresponding antiparticle, they mutually annihilate and all of their combined mass is converted into energy in the form of electromagnetic radiation (photons) according to Einstein’s famous E = mc² equivalence. For this reason, antimatter must be kept shielded from all ordinary matter, including air, which means keeping it suspended or circulating in a vacuum. This can only be achieved via magnetic fields in the case where the antimatter has an electric charge. The energy release involved is huge: half a milligram of matter brought together with half a milligram of corresponding antimatter will release enough energy to power a 2 kW heater continuously for about 520 days.
'Luthon64
"Sensitive" people are now carefully examining the entire universe, trying to find something to be "offended" at. It won't stop until such time as the "offenders" learn to stop apologizing, and saying "freck off" instead. — brianvds, The ShoutBox Classics, 02/07/2018.