Astronomers have for the first time “X-rayed” a galaxy to directly measure
its oxygen content by using a quasar like an X-ray machine. The discovery,
which could have been made only by X-ray observation, demonstrates a new way
to get chemical information needed to understand how galaxies evolve.
They made a second major discovery, too: They discovered what was believed
to be a relatively quiescent type of infant quasar to be producing an
enormous X-ray jet, at least a million light years long. The result
overturns a branch of quasar lore that says a certain type of
dust-enshrouded quasar is too young to be very active.
Jill Bechtold of the University of Arizona and Aneta Siemiginowska of the
Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., collaborate
in quasar surveys using NASA’s Chandra X-ray Observatory and Hubble Space
Telescope.
