That white glow is often the first thing people see around others, without realising it is the aura! I saw that as a child and never knew what it was.
A way to make sure it's not just an after-image is to blink or look away and back. If it remains, then it's the aura.

When watching someone speaking, such as a teacher, you will also often see a pale yellow around their heads. I associate this with use of the intellect. If you ease your focus and relax, other colours may come to mind. Try looking at someone's profile when in a car or train. You might see a pale blue line around their skin - the electromagnetic field.

Lie under a tree and focus just beyond the edge of the leaves... you'll see a translucent 'rim'. I often catch a glimpse of a soft lilac around trees, about 30 feet above them and have seen the aura of flying birds. It's cool.