His goal was to use HST's sharp vision to image the galaxies which, according to current theories, should act as hosts for the quasars insofar as they would provide fuel for the presumed supermassive black hole at the heart of the quasar.
Host galaxies are hard to see because of the glare from the quasar itself.
In Bahcall's sample of 14, several host galaxies were found, but for 8 quasars no hosts were found. The new models show what happens when the massive outer portion of a dying star falls in on the blizzard of neutrinos streaming out of the just-collapsed core. At the AAS meeting, Adam Burrows and Willy Benz of the University of Arizona and Marc Herant of Los Alamos showed off their multi-dimensional models allowing colossal convective plumes of rising hot material and sinking cool material to interpenetrate, facilitating a more efficient movement of explosion energy. Left unstirred, the sauce will burn on the bottom and be cool on top. This works out to a density of 100 million solar masses per light year, a density some 10,000 times greater than that of any known cluster of stars.