My thoughts, from my experience and knowledge from books and classes:
Anything and everything IS energy, there is no matter
Okay okay, what I meant to say is that whatever we call matter is merely manifestation of energy on various levels and planes. For the same reason everything - living and non-living - have energy. If they have energy, they have an energy field as well. As a Pranic Healer this is also the reason why I can scan and cleanse various things, apart from living bodies.
So is Aura the energy or is that an energy field? To understand it better, what is an energy field but an area where we can "feel" that energy? So Aura is the energy itself, which acts as an energy field which we can "feel" and "measure".
Another question is if Aura is being emitted from the object? Not really, it is when energy manifest that object is formed. It is the energy in play not the matter. The moment the energy disperse the matter withers.
I guess more people can pool in thoughts?