SpaceX launched 24 more of its Starlink internet satellites from Vandenberg Space Force Base today (Sept. 2), sending them up on a Falcon 9 rocket with a brand-new first stage.
Around 11,300 years ago, a massive star teetered on the precipice of annihilation. It pulsed with energy as it expelled its outer layers, shedding the material into space. Eventually it exploded as a supernova, and its remnant is one of the most studied supernova remnants (SNR). It's called Cassiopeia A (Cas A) and new observations with the Chandra X-ray telescope are revealing more details about its demise.
