We read that spiral galaxies have blackholes at their cores. I don't
hear that elliptical galaxies have blackholes at their cores.

just take o look on matter burst from galaxy M87 - it's huge elliptical
galaxy and that burst is from supermassive black hole in its core. Not all
of spiral galaxies have its own supermassive BH in its core. M31 yes, our
Galaxy propably yes but M33 not and so on

I read that elliptical galaxies are created when two spiral galaxies
collide(come to gether) That means they can have two blackholes
revolving around each other. This could create a very bright core.

NOT TRUE. Astronomers don't know how the evolution goes at galaxies, but it
seems, that spiral galaxies are envolving through time from some elliptical
galaxies (and some elliptical galaxies stayed elliptical). By the way - BH
in center of a galaxy is no reason for some 'bright core'

I saw a picture of elliptical galaxy NGC 147 and that is how I came up
with this thinking.

elliptical galaxy NGC 147 is no good example. This is one of many and many
dwarf galaxies, these are to small to evolve to any galaxy with spiral
structure. There is a huge difference between 'normal' elliptical galaxies
(like M87) and dwarf elliptical galaxies (like these two 147 and 185). By
the way, these two a actually satelites of our Galaxy and it's gonna swallow
them both in time.


Mysak