Rare 'firework morphology' of supernova remnant Pa 30 may be due to white dwarf wind

In 1181 AD, a bright "guest star" was observed to linger in the sky for around six months. Nearly 850 years later, the likely remnants of this event were rediscovered and tentatively linked to the 1181 supernova and dubbed supernova remnant (SNR) Pa 30. Yet, this supernova remnant was unique in appe…