Like a bright city in the middle of a barren desert, our galactic neighborhood is enveloped by a cosmic void — an enormous, almost unfathomably empty pocket of space. Recently, sky surveys have spotted thousands more of these vacant bubbles. …
For around 20 years, astronomers have struggled to find an ancient group of stars mixed in with the gas, dust and newer stars of our galaxy’s bulge. These “fossil” stars preceded the Milky Way and should have been discernible by …
Every year, around 1,000 Type Ia supernovas erupt in the sky. These stellar explosions brighten and then fade away in a pattern so repeatable that they’re used as “standard candles” — objects so uniformly bright that astronomers can deduce the …