Ask Ethan: If Dark Matter Is Everywhere, Why Haven’t We Detected It In Our Solar System?
It’s the first, most naive question you might think to ask. The solution is a lot more complicated than you imagine.
According to a large amount of evidence, the overwhelming majority of the Universe is made out of some mysterious type of mass that we’ve never directly measured. While protons, neutrons, and electrons — and for that matter, all the matter made out of particles from physics’ Standard Model — make up the planets, stars, and galaxies we find throughout the Universe, they compose only 15% of the Universe’s total mass. The rest is made out of something entirely different: cold dark matter. But if this dark matter is everywhere and so abundant, why haven’t we seen it in our Solar System? That’s the question of Bob Lipp, who wants to know:
All the evidence for dark matter and dark energy seem to be way out there in the cosmos. It seems very suspicious that we don’t see any evidence of it here in our own solar system. No one has ever reported any anomaly in the orbits of the planets. Yet these have all been measured very precisely. If the universe is 95% dark, the effects should be locally measurable.
