Name: paul gilbert
Date: 1993 - 1999
How are quasars powered and what causes their intense luminosities. Is the quasar actually a small galasy in itself or a forming star?
Quasars are now thought to be galaxy-like rather than star-like,
although the name comes "quasi-stellar object." When first discovered
in 1965 (by a graduate student!) they were thought to be nearby
stellar objects because of their luminosity and size (they appeared
as point sources like stars), but they had extremely high red shifts
which usually indicates extreme distance. If they are far away, then
their energy output is ENORMOUS. We really don't know what their power
source could be except to say that it probably involves one or more
massive black holes. But that's really just a guess because we don't
know of any physical mechanisms that can produce so much energy
from a something the size of a galaxy for a long period of time.
One idea is that quasars are galaxies in a very early stage of development.
Their extreme distance makes them extremely old. If you believe
in a continuous morphology of galaxies and similar objects, then
"Seyfert galaxies" may be what quasars evolve into.
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