Zinnias have opened their petals for the first time on the International Space Station, and NASA astronaut Scott Kelly couldn't be prouder.
Pluto's the prettiest dwarf planet at the party in this new, brilliantly colored image recently released by NASA.
A "zombie" star and the remains of its lunch are revealed in a new close-up view, 12 years in the making.
The ancient lunar surface once erupted with geysers of lava — and now, scientists think they know what caused these fiery fountains.
The Deep Space Climate Observatory spacecraft recently caught the moon crossing Earth's face in a stunning video that shows off the mysterious lunar far side.
Blasting tiny, waferlike sailing spacecraft with powerful lasers could slash interstellar flight times from thousands of years to mere decades, one researcher says.