Set smart quides and snap to point ON, snap to grid must be off!
Draw a quide star. That fits perfectly inside a circle when centered. In my example I have drawn a an yellow 11 branch star that has the wanted outer radius.
Draw a star to be placed. Draw two diagonals inside it. This way you get a solid centerpoint to be dragged precisely. Remove their strokes and group them with your star. I have left the stroke visible for easy watching. NOTE From Attributes panel it's possible to turn on star's own centerpoint, but it's not the same as the crossing of the diagonals. Surely that point has its reasons, but they are not visually simple like the crossing of the diagonals
Make a series of copies by blending to get different sizes. Expand and ungroup.
Alt drag (=drag copies) of the stars to the vertices of the quide star. Kill the quide star when you are sure that you do not need it.
Approach the quide star from outside to avoid selecting it. You can't lock it.
Until this there is no more than the blending offers, only one possible solution that's asked. But the major idea, the help diagonals for exact placing gives different development possiblities than the blending. A couple of elementary examples:
The colour things, shape evolution and rotations can be done when creating the series of the stars