Oftentimes, we think of space as an endless, mostly empty vacuum, a silent backdrop where planets, stars, and galaxies play out their dance. We also think of time as something separate, a steady ...

Whether space-time exists should neither be controversial nor even conceptually challenging, given the definitions of “space-time,” “events” and “instants.” The idea that space-time exists is no more ...

The ISS has “come into its own as a very sophisticated scientific laboratory,” says retired NASA astronaut Scott Kelly, who ...

The International Space Station is one of the most remarkable achievements of the modern age. It is the largest, most complex, most expensive and most durable spacecraft ever built. Its first modules ...

Follow the space program since the moon landing in the four-part documentary "Once Upon a Time in Space". Here’s how to watch ...

Since the first crew of astronauts reached the International Space Station on Nov. 2, 2000, humanity has had a continuous ...