Quote:
Originally Posted by ANLWhip
#1 is there a black hole in the center of the Milky way?
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As already said, yes, it is pretty clear that there is.
Quote:
Originally Posted by ANLWhip
#2 does the gravitational power projected by this mass ( if it exists )
form a " thin plane " projected out from the center of the Galaxy?
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The term you wanted was probably "force" rather than "power".
Gravity is a force, but exists without expenditure of energy. Power
is a measure of the rate of energy expenditure.
The gravity of the black hole at the center of the Milky Way is
essentially spherically-symmetric.
The galaxy is flattened out like a pizza crust not because it
experienced forces like pizza dough being spun, but because of
friction between the gas and dust particles as the galaxy formed.
The particles were initially moving in all directions, randomly, but
as gravity pulled them together, they collided more and more often.
The result of the collisions was the formation of a rotating disk.
Particles in the disk are all moving in about the same direction, so
they don't often collide. Particles moving at an angle to the disk
collided with particles in the disk, so they ended up as part of the
disk. The angular momentum of particles in the original cloud and
the orientation of the disk that collapsed from the cloud together
determined how the particles are distributed throughout the disk.
Quote:
Originally Posted by ANLWhip
and finally
#3 does our solar sytem pass through this theoretical plane in 2012?
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The Milky Way's disk is very roughly 2000 light-years thick. We
can probably determine the centerline of the disk near our position
to an accuracy of plus or minus a few tens of light-years. It takes
many thousands of years for the Solar System to pass through
that distance, so it isn't possble to state the exact date, or year,
or century, or even millenium of such a passage. The last such
passage was many millenia ago, and we have been moving away
from the central plane ever since. Our speed away from the central
plane is slowing, though, and eventually we will begin moving toward
it again, and pass through it several million years from now.
The passage in 2012 of the Sun across the galactic plane is just
our view of where the Sun appears relative to the stars in the
distant background. It is about as meaningful as crossing the
Earth's equator. The line that the Sun crosses is an imaginary
line in the sky, and it crosses that line twice every year.
The passage in 1998 of the Sun across the galactic plane that
tusenfem referred to appears to be the one in recent times that
aligned most closely with the galactic center. ***Grant or someone
correct me if I have that wrong -- My sky map for 1998 doesn't show
that clearly. Neither the galactic plane nor the center are marked on
the map, so I'm interpreting the galactic co-ordinates from another
source.***
In any case, it was just that the Earth, the Sun, and the center
of the galaxy were momentarily lined up like you, a car going past
you on the road, and a distant water tower will be momentarily
lined up. There is no significance to the alignment. A person on
Mars would not see the alignment. Similar alignments happen
every day all around our Solar system for the various planets and
asteroids, and that is probably true of every planetary system in
the galaxy.
Quote:
Originally Posted by ANLWhip
since russia recently pulled another fully frozen mastadon with
vegitation undigested frozen in its throat, it begs the question
" what power in the universe would effect such a quck change?"
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As others suggested, the animal was probably a mammoth rather
than a mastodon, and the vegetation was more likely found in its
stomach or intestines than in its throat. But I don't know anything
about mammoth digestion. They may have regurgitated cud. Or
the animal could have regurgitated as a result of freezing to death.
According to this web page:
http://elephant.elehost.com/About_El...ve_system.html
not much digestion takes place in an elephant's stomach. I expect
that mammoths functioned the same way.
Since the animal was found still frozen after thousands of years in
permafrost, it seems quite likely that it died the year the surface
became frozen year-round at that location, as the last ice age was
coming on. It might have drowned in a bog, or just frozen to death.
That doesn't sound like a particularly unusual event.
Quote:
Originally Posted by ANLWhip
and since man evolved and lived with and hunted these creatures,
this must have happened in so relatively recent history so, is it
possible that it wil happen again?
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Every day. Animals drown or freeze to death all the time. Since
mammoths became extinct several thousand years ago, though,
there won't be any mammoths drowning or freezing in 2012.
-- Jeff, in Minneapolis