T Pyx: Death By a Thousand Novae

T Pyx is the Galaxy's most famous recurrent nova. Six times since 1890, it has erupted to 6th magnitude, then slowly returned to its quiescence near V=15.5. It's a compact binary of very short orbital period (1.7 hours), and that period increases rapidly. From the luminosity and rate of period change, we learn that the accretion rate in ~2x10**-7 Mo/yr, about 4000x greater than cataclysmic variables of similar orbital period. The change in P_orb after outburst reveals the mass ejected to be 10**-4 Mo. This suggests that T Pyx is rapidly headed for a death not by fire (a Type Ia SN), but rather by ice (evaporation of the secondary in an ever-widening spiral). This may be the fate of all cataclysmic variables accreting hydrogen.

Followed by wine and cheese in Pupin 1402.

More Events »