The solar system moved through a star-forming area near Orion. This event might have increased interstellar dust around Earth.

One million alien visitors from another star system could already be lurking in the solar system. We aren't talking about "little green men" here, however — more "little (and not so little) gray rocks," asteroids from the triple star system Alpha Centauri.

The discovery that helium and iron can mix at the temperatures and pressures found at the center of Earth could settle a long-standing debate over how our planet formed.

Interstellar material has been discovered in our solar system, but researchers continue to hunt for where it came from and how it got here. A new study led by Western astrophysicists Cole Gregg and Paul Wiegert recommends Alpha Centauri—the next closest solar system to ours—is a great place to start,

Researchers claim that there could be at least 1 million interstellar objects hiding in the Oort Cloud at the edge of our solar system.

Scientists have confirmed a 19-year-old theory on solar flare formation by observing “slip-running” reconnections in the sun’s magnetic field. An international research team, including an astrophysicist from Oregon State University,

Millions of years ago, our Solar System traveled through a densely populated galactic region and was exposed to increased interstellar dust.

The Oort cloud is a shell of icy objects that forms the very outskirts of our Solar System. Recently, a group of researchers discovered that the inner portion of the Oort cloud likely has spiral arms that make it look like a galaxy.

Using a NASA supercomputer to run models, researchers led by SwRI astronomer David Nesvorny now believe that the Inner Oort cloud looks like a spiral disk, around 0.24 light-years across, with two arms like many a galaxy, albeit oriented vertically.

In research highlighted in a new paper, published today in The Astrophysical Journal, Scientia Senior Lecturer Ben Montet and PhD candidate Brendan McKee analysed changes in the timing of a known planet's transit across its star, to infer the presence of a second exoplanet.

The mysterious Oort cloud is the source of many of our solar system's comets, but astronomers still have no idea what it looks like. Now, new simulations may have given them a first glimpse.