Lighting, want to have glowing sphere

Im writing a Sim of our solar system.
So I want to have it lit up by our sun!

I tried various things (alphablending etc.)
to create a sun with a diffuse light source in it. I thought the light in opengl is only reflected by surfaces whose normals go in the opposite direction of the light.
So I created a simple solid sphere with a diffuse light source in it, but the scene is completely dark now…
Can anyone tell me how to create a glowing Sphere?

Thx in advance for help.

give the sun a GL_EMISSION value.


glMaterialfv(GL_FRONT, GL_EMISSION, mat_emission_value);

You can make it look like it is giving off light of some color.