Can humans have babies on Mars? It may be harder than you think.

To build a sustainable presence off Earth, humans will first have to answer some tricky questions about basic biology.

Both of NASA's Voyager spacecraft are now interstellar. Where to next?

Launched in 1977, the twin probes will likely outlive the sun. Find out what star systems they’ll meet as they head deeper into the galaxy.

Gamma-Rays Spewed As a Black Hole Forms Might 'Reverse Time'

The researchers said they have no idea what's causing these time-reversed gamma-ray signals, but they added that the physics around black holes are so strange that nothing can be ruled out.

What dogs hear when we talk to them

Scientists have shown that young dogs respond to this way of talking, and that it may help them learn words