NASA plans to launch a new x-ray telescope this week to help answer questions like what’s inside a black hole and how bright pulsars can get.   On Thursday, December 9, the agency will launch the Imaging X-ray Polarimetry Explorer, known as IXPE, on a Falcon 9 rocket from NASA’s Kennedy Space Center in Florida. It will be the first x-ray telescope capable of measuring polarization, a property of…