I want to address this by making a huge leap of the imagination. We do know by making standard assumptions and by routine modeling that we cannot account for about 85% of the mass necessary to produce the universe we see.
Yet all our knowledge of physics is based on what we can detect and then obviously measure. Another way of looking at this is that we detect HOT particles.
Now what about COLD particles. I already know that we know hydrogen exists everywhere and we can not readily detect an individual atom without reacting it. Hydrogen by itself is a COLD particle as is every non - ionized element.
Now suppose that we only measure HOT particles and every particle type is more commonly COLD. Our whole Solar Systerm could be an ocean of neutral neutrinos produced by the prodidious output of our SUN. these particles naturally self assemble to produce all our our particles including neutron pairs which can decay into hydrogen.
Since the majority of such matter is COLD, light would pass through unimpeded.
If all stars and really STARS can be described through Cloud Cosmology, then they all sustain a massive halo of COLD matter that may not extend much beyound the known limits of our Solar system which we have already sort of detected. It also explains why we have a real bow wave out there that may well be more material than expected.
By the way, does our physics adequately describe what we are detecting? Why do we have a bubble protecting us and just what is producing it? It carries a powerful magnetic field as well.