How fast is the universe expanding? The mystery endures

Scientists have known for decades that the universe is expanding, but research in the past few years has shaken up calculations on the speed of growth—raising tricky questions about theories of the cosmos.

From primordial black holes new clues to dark matter

Primordial black holes (PBHs) are objects that formed just fractions of a second after the Big Bang, considered by many researchers among the principal candidates in explaining the nature of dark matter, above all following ...

NASA's WFIRST will help uncover the universe's fate

Scientists have discovered that a mysterious pressure dubbed "dark energy" makes up about 68% of the total energy content of the cosmos, but so far we don't know much more about it. Exploring the nature of dark energy is ...