August 20, 2019

02.04.10- Cassiopeia A: A Quark Star?

The supernova remnant Cassiopeia A holds a compelling astrophysical mystery. Located about 10,000 light years away, this strong radio source was identified in 1947 and remains the most recent galactic supernova known. One slightly odd fact revolves around Cas A; despite its having burst about 325 years ago as seen from Earth, no reliable records exist of the event. Evidence of the event may have been obscured by intervening galactic dust.  Some intriguing indications show that John Flamsteed may have misidentified the supernova as a sixth magnitude star in Cassiopeia during one of his surveys, but now Cas A may be the home of a even more bizarre denizen; a quark star. This theory stems from the fact that the remnant host appears to be only 10 km across, smaller than your average neutron star. At that density, neutrons loose all individual identity and merge into a huge ball of quark strange matter, a “strange” object indeed. First spotted by the Chandra X-Ray observatory in 1999, this “quark star” would be the first of its kind. Of course, an alternative hypothesis, put forth by Wynn Ho and Craig Heinke of Southampton University, states that we’re merely seeing a normal neutron star of about 25 km in diameter shining through a carbon atom haze. Does astrophysics need to get any weirder?