Dense pools of dark matter are yanking on galaxies deep in space. Astronomer Catherine Heymans talks about mysterious force of dark matter.

In the far future, a giant cloud of hydrogen will collide with our Milky Way galaxy and help create thousands of new stars.

Astronomers have identified the telltale sign of a possible hypernova - a huge stellar explosion - in one of our galaxy's oldest stars.

Are we alone in the universe, or is there intelligent life out there? And if so, how would we find it? Read more about habitable zones on distant worlds.

A dwarf galaxy in the direction of the constellation Pegasus is being stripped of its gas, according to astronomers. A galaxy needs its gas to create new stars. So we might be seeing this galaxy near the end of its ability to form stars.

An astronomer has found four stars in a tight orbit that might help unlock secrets of how stars evolve. The system is BD -22°5866, and astronomers thought it was one star.

GRAIL, set for launch in 2011, will measure gravity and map the moon's gravity. It consists of two satellites that'll orbit the moon for about 90 days, like a pair of mini-moons of the moon.

This object called SDSSJ0946+1006 is the first-ever double 'Einstein ring.' It looks like a double ring around a bright center. There are thought to be three objects here - a distant galaxy that warps the light of two more galaxies exactly aligned behind it.

How does a ring-shaped galaxy form? It might result from an impact with another galaxy slamming into its center. Read more about ring galaxies.

HD 74156 is a distant planetary system that seemed to have a large gap between two known planets. Astronomer Rory Barnes predicted a planet there and thus become the first to find a planet outside our solar system by predicting its location in advance. That hasn't happened since astronomers found Neptune in our own solar system in the year 1846.