Every object in this world, whether it is animate or inanimate, radiates energy in all directions and in the same shape as itself. These radiations are waves of electromagnetic energy and they constitute the aura. Nothing in this world exists which does not radiate energy.
The aura of a living organism is produced by the radiations coming from its subtle body - taijasa sarira. In this case, together with the electromagnetic energy, vital energy (prana) is also radiated. Hence, the aura of an organism is bright, dynamic and radiant while that of an inanimate object is dull and static. The aura of an organism is not static but dynamic: Contraction, expansion, contamination and purification - all these continuously occur in it. This is because within the organism there exists the domains of lesya and emotions which keep it ever-changing. That is a factor of distinction between an organism and an inanimate object, i.e. the latter does not possess a change-producing factor.