Space

The halo of stars that envelops the Milky Way galaxy is like a river delta criss-crossed by stellar streams large and small, according to new data from the Sloan Digital Sky Survey (SDSS-II). While the largest rivers of this delta ... [full story]

For almost thirty years, scientists have known that complex carbon compounds called tholins exist on comets and in the atmospheres of the outer planets. Theoretically, tholins might interact with water in a process called hydrolysis to produce complex molecules similar ... [full story]