A tip o' the hat to Miss Nancy;  she has the atmosphere issue covered -  it won't work for this (I had in mind a point light within the ball).

The reason for using two edge blend nodes is to avoid obliterating your view of the ball.  The center of the aura is empty, so to speak.  Notice that you can easily see the fiery ball.  If this is not a needed feature, then Rooster's single node will be simpler.

Widen (or narrow) the corona by adjusting the attenuation values in either/both of the edge blend nodes.  You can resize the outer (aura) ball if you need more of a gap than adjusting the attenuation allows.

Adjust the transparency of the corona by slightly greying down the white color in both of the edge blend nodes.  Go easy;  a little dab'll do ya.

The fiery texture is a simple procedural - I use it a lot for still images.

Poser 12, in feet.  

OSes:  Win7Prox64, Win7Ultx64

Silo Pro 2.5.6 64bit, Vue Infinite 2014.7, Genetica 4.0 Studio, UV Mapper Pro, UV Layout Pro, PhotoImpact X3, GIF Animator 5