Mom, I thought you should know something about the universe. In the 1970s, astronomers began noticing something that didn't seem to fit with the laws of physics. They found that spiral galaxies like our own Milky Way were spinning at such a rate that they should have long ago wobbled out of control, shredding apart, shedding stars in every direction. Yet clearly they had done no such thing.

They were living fast but not dying young. This seeming paradox led theorists to wonder if a halo of a hypothetical something else might be cocooning each galaxy, dwarfing each flat spiral disk of stars and gas at just the right mass ratio to keep it gravitationally intact. Borrowing a term from the astronomer Fritz Zwicky, who detected the same problem with the motions of a whole cluster of galaxies back in the 1930s, decades before anyone else took the situation seriously, astronomers called this mystery mass "dark matter."

This is terribly important, Mom, for the future of the Mudcat and everyone in it.


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