One of the serious problems with measuring the speed of light is that it really isn’t the constant we all claim it to be as we know that light is altered by the medium through which it travels, otherwise lenses wouldn’t work, light would bend on entering water, red shift shouldn’t occur, etc. We think that the speed of light is ~186,282.25 miles per sec in a vacuum everywhere but we really have only tested here in our backwater province which, for all we may know is a school zone with a speed limit sign. In other words, we are making unwarranted assumptions that local conditions are universal. There is no legitimate reason to accept those assumptions.
One of the biggest ones is the use of G as a constant in many universal equations. That’s "Big G" as in the force of Gravity, which assumes G is a constant. In general, for most things, it works fine. Many people even here on earth use G as 1G, but G measures slightly differently everywhere it’s measured accurately on earth. It also varies with time. It certainly is not the same big G everywhere in the solar system. . . and one of the shocking things predicted by the EU, which is being found to be true in visits to comets, G may not be related to mass, and mass may ultimately be related to charge differential.
Incidentally, no model of the accretion disk star and planet formation has ever been shown to actually come to cause the creation of a star or planet. Instead, they tend to fall apart, not coalesce. The tendency to all orbiting gases and solid particles to orbit at the same velocity and orbits is part of the problem. The lack of high enough differential velocities at micro-gravities show that collisions tend to just bounce apart at such low velocity and not adhere. The bounce may result in a mutual orbit around a shared center of gravity, but only rarely would two masses join. Some force stronger than gravity is required to form planets and stars.
Eh? What force is stronger than gravity?
oh wait...