The Cosmos' Greatest Mystery Deepens
The galaxy of Andromeda, the nearest large galaxy to our own, circa 1990
Space Frontiers / Hulton Archive / Getty Images
Like Hollywood legends Audrey Hepburn and Katharine Hepburn, dark energy and dark matter are completely unrelated, even though they share a name. Dark energy, a force that makes the universe expand faster and faster all the time, is called dark because it's mysterious. Nobody knows what it is. Dark matter, on the other hand, a type of matter that outweighs ordinary stars and galaxies 5 to 1, is called dark because it's utterly invisible. We know it's there because its gravity yanks galaxies and stars around, but it neither emits nor reflects any light.
Labels: universe
posted by Aloyzio Achutti at 11:36 AM
0 Comments:
Post a Comment
<< Home