Add Yahoo as a preferred source to see more of our stories on Google. Dark energy is one of the most mysterious concepts in all of the cosmos. We know very little about what it is but it just might ...

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 ...

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to [email protected]. How will the universe end? – Iez M., age 9, ...

After the Big Bang, the Universe entered a long, dark period before the first stars formed. During this era, hydrogen emitted a faint radio signal that still echoes today. New simulations show this ...

Astronomers used the James Webb Space Telescope and gravitational lensing to observe SN Eos, an ordinary supernova from the ...

The surface of Earth is finite. We can measure it. If it was expanding, then its size would grow with time. And once again, good ol' Earth helps us understand what the universe might be doing beyond ...

There may not be as nearly as many small galaxies in the early universe as astronomers predict there should be, which has big ...

Calculating the total mass of the universe is not simple, because most of the mass is invisible. In a pie chart of the contents of the universe, only 5 percent is normal matter, atoms that make up all ...