Another rant on dark matter

In regard to dark matter, you could say, “Well, astronomers were able to predict the existence of planets in our solar system that had not yet been directly observed, because the unseen planets perturbed the orbits of already-observed planets. It’s the same situation with dark matter. We know its there because it’s perturbing the motion of visible matter in distant space.”

But it’s not the same situation. Where unseen planets are concerned, astronomers weren’t positing the existence of a new form of matter with very unusual properties. They were merely saying, “There should be a planet in this orbit, because the orbit of this other planet doesn’t quite fit theory.” There’s nothing wrong with that type of prediction. But with dark matter, scientists aren’t doing that. They’re saying, “There should be a completely new form of matter with very unusual properties all around us, because the motion of distant matter isn’t behaving according to theory.”

Now, if the planet-hunting astronomers had said, “There should be a completely new form of matter with very unusual properties in this orbit, because the orbit of this other planet doesn’t quite fit theory,” it would be a different story. THAT would be an absurd, unwarranted leap of logic, and it’s precisely the leap scientists are making when they concoct dark matter to patch the hole in their Big Bang theory. 

The reason scientists aren't resorting to everyday, familiar objects to explain the motion of distant matter is because the discrepancies between observed and predicted motions aren't the only problems faced by cosmologists. Dark matter is being invented to explain other discrepancies as well. Ordinary matter won't fit the bill.