Imagine waking up one morning to find our Sun replaced by a cosmic powerhouse far stranger than anything we have seen. From ...

Astronomers are closing in on what looks like a rare prize: a world almost the size of Earth, circling a Sun-like star at a distance that gives it a familiar, year-long orbit. The candidate, known as ...

The object, the latest “quasi-moon” detected by astronomers, could be with us for almost another 60 years. By Robin George Andrews The Earth stands alone in the solar system as a habitable world, as ...

Earth's shadow follows the planet as it orbits the sun. You can get a sense of its enormous, awe-inspiring size by seeing ...

The Earth stands alone in the solar system as a habitable world, as far as we know. But that doesn’t mean we don’t get visitors, most often in the form of (usually harmless) asteroids. Some even ...