Well that's not quite how reflections work.
What you're talking about is more a whole new function of TG to capture reflection points of origin to be able to differentiate from something like bare sky, and a surface reflection.
Not really a material.
Also, at these scales, reflections don't work that great. Take a sphere for example with a disc surrounding it giving off light. Put it in a black void (no sun, looking top down with disc in view around the sphere) and it will reflect the camera's viewport on the center of sphere, rather than the disc reflecting off the sides of the sphere warping to the center. There will be no reflection from the disc itself on the sphere, but a weird duplication of the scene.