Add Yahoo as a preferred source to see more of our stories on Google. In space, there are four dimensions: length, width, height and time. scaliger/iStock/NASA via Getty Images Plus About a century ...

IT IS ONE of the biggest mysteries in cosmology—and getting bigger all the time. Ever since Edwin Hubble, an American astronomer, published observations of distant galaxies in 1929, scientists have ...

Neutrinos are one of the most elusive and omnipresent particles in the universe. Their strange properties may explain why the amounts of matter and antimatter in our universe aren’t equal, as most ...

Astronomers are using radio pulses from space to find missing baryonic matter and learn about supermassive black holes, stellar formation and galaxy evolution. When you purchase through links on our ...

The way time ticks forward in our universe has long stumped physicists. Now, a new set of tools from entangled atoms to black ...

Here’s what you’ll learn when you read this story: A new paper adjusts an equation that defines our universe in response to recent new data. The cosmological constant, which describes how our universe ...

There may not be as nearly as many small galaxies in the early universe as astronomers predict there should be, which has big implications for the story of how our universe grew up. When you purchase ...