by Mark Walker (Manly Astrophysics)

Abstract. In February the ATESE project discovered extreme scintillations in a quasar only 8.5 arcmin from Spica – one of the brightest stars in the sky. By itself that coincidence is surprising, but not compelling. However, another look at the properties of the two best-studied intra-hour variables (PKS1257-326 and J1819+3845), confirms the association between extreme scintillation and hot, local stars. I’ll present the evidence for that conclusion, and describe what it tells us about the circumstellar environment, etc.