Astronomers may have found the long-missing half of the universe's regular matter—and it appears to have been right under our ...

For decades, scientists have known that ordinary matter — everything made of atoms — accounts for just 15% of the universe’s matter. The rest is mysterious dark matter. But even that modest slice didn ...

"The new model can account for both structure formation and stability, and the key observational properties of the expansion of the universe at large." ...

You may have seen a meteorite before, even if you didn’t know it. Nearly 100,000 pounds of meteoritic matter enters Earth’s ...

A group of comets with unexplained movements presents a quandary D avide Farnocchia hunts down and tracks asteroids, and several years ago he saw something he couldn’t explain. Farnocchia works at ...