Footage shows the 13th mission of Artemis 1, where the Orion spacecraft captures Earth slipping behind the moon. The footage ...

Planetariums were a hit with the public. Within decades, they had spread around the world – the first planetarium in the ...

As America prepares to celebrate the 249th anniversary of the Declaration of Independence – a document steeped in the ...

A leap second is a one-second modification that is sometimes used with atomic clocks, whenever there is a change in Earth's ...