Longtime NASA astronaut Don Pettit, who has ventured to space four times, returned to Earth on Saturday night from the ...

Photographer extraordinaire Don Pettit is about to return to Earth following a seven-month stay aboard the space station. Take a moment to enjoy his best work.

In a discovery that could reshape our understanding of how galaxies form and evolve, astronomers have identified the most distant spiral galaxy candidate ever observed—a vast, mature system that ...