Dark Matter May Collide With Atoms Inside Human

Invisible dark matter particles may regularly pass through our bodies, and dozens to

thousands of these particles may be colliding with atoms inside us every year, according to a new calculation. However, radiation from these impacts is unlikely to cause cancer. Dark matter is one of the greatest scientific mysteries of our time, an invisible substance thought to make up five-sixths of all matter in the universe. Scientists think it might be composed of things called weakly interacting massive particles, or WIMPs, that interact normally with gravity but very weakly with all the other known forces of the universe. Its ghostly nature makes it exceedingly difficult to directly prove whether dark matter really exists or what its properties really are. Dark matter is largely thought to be intangible, its presence detectable only via the gravitational pull it exerts. Still, although dark matter particles are thought to interact only very rarely with normal matter, Earth and everything on it should be hurtling through a dense sea of dark matter, with billions of these particles rushing through us every second. Though the large majority of these particles would pass straight through us without hitting any of the atoms that make up our bodies, a few collisions would be likely. And the aftermath of such impacts could shed light on dark matter’s nature. Scientists calculated how many times dark matter particles ought to collide with atomic nuclei in adult-size bodies, lumps of flesh about 154 pounds (70 kilograms) in mass largely composed of carbon, hydrogen, oxygen and nitrogen.