5*2=10 corners in total
Stars are spherical bodies and have no sides nor corners.
If you meant "corners" as points, the Star of Bethlehem was always regarded as an 8-Pointed star. In Greek, writing the name of Christ sums up to 888. All baptismal fonts have 8 corners.
A 3D star is not a standard shape. You can easily add another point.
A traditional star has five points. A star of david has six. A star must have at least five points, but can have infinately more. Depends on what you mean by a star. For instance are sun has no corners. But the standard way to draw a star is with 5 corners.
The magen star is the star of David - a star with 6 corners
The astronomical object does not. A model does.
As many corners as sides.
8 corners
It has 4 corners
8 corners
a cylinder has no corners