Astronomers have long known the universe is expanding—but exactly how fast remains one of the biggest mysteries in cosmology. Different techniques for measuring the Hubble constant stubbornly disagree ...

For decades, astronomers have known that the universe is expanding. To determine how fast it is growing today, scientists calculate a value called the ...

Astronomers use telescopes to look back in time and observe stars and galaxies as they were millions and billions of years ...

We should not despair that we live in a universe which is beyond our understanding. We can in fact be confident that we do understand much about how the universe works ...

Einstein famously said, “Time is a tremendously persistent illusion.” In a 1955 letter, he added, “For those of us who believe in physics, the distinction between the past, present and future is only ...

The first bubble of hot gas seen around another star has been spotted around the "Moth," just 117 light-years away.

Bode’s Big Night. On December 31, 1774, Johann E. Bode discovered both M81 and M82. In 1779, Pierre Mechain independently ...