It was a mission that lasted far longer than planned ... longest-serving NASA astronauts in space on a single mission. The ...

The X-37B spacecraft’s latest mission was shorter than the last but tried several new maneuvers and approaches during its ...

And empty space continued to expand ... galaxies requires knowing how far away those galaxies actually are. Astronomers use something called the cosmic distance ladder to connect observations ...

The boundaries between planet Earth, the moon, and deep space just got fuzzier ... than 20 years ago, the outer fringes of our cozy planet's atmosphere stretch far beyond what is typically ...

During this circuit, our planet is an average of 93 million miles away from the sun, a distance ... outer core lies the mantle, a 1,800-mile-thick layer of viscous molten rock on which Earth's ...

When US astronauts Barry “Butch” Wilmore and Sunita Williams touched back down to Earth after their prolonged nine-month stint in outer space ... may seem like a far stretch from reality ...

The postponement, driven primarily by thick clouds, was the second scrub of the flight since an issue with the rocket on Saturday night.