Most of the dwarf planets now have known moons
Beyond the orbit of Neptune lies a frigid, dark, vast frontier of countless icy bodies left over from the solar system's construction 4.6 billion years ago.
Hubble Celebrates Its Anniversary with a Spectacular Pair of Galaxies
When the Hubble Space Telescope launched aboard the Space Shuttle Discovery on April 24, 1990, astronomers could only dream what they might see.
Best Evidence Yet for Reoccurring Water Vapor Plumes Erupting from Jupiter’s Moon
When Galileo discovered Jupiter's moon Europa in 1610, along with three other satellites whirling around the giant planet, he could have barely imagined it w...
Energetic Event 'Burped' Billowing Plasma Bubbles 6 Million Years Ago
About 6 million years ago, when our very remote ancestors began to evolve away from chimpanzees, our Milky Way galaxy's hefty black hole was enjoying a sumptuous feast.
The Versatile Space Telescope Imaging Spectrograph (STIS) Opens New Vistas in Astronomy
Twenty years ago, astronauts on the second servicing mission to the Hubble Space Telescope installed the Space Telescope Imaging Spectrograph (STIS) aboa...