History Channel
Season. 01 Episode. 09
http://www.history.com/shows/the-universe
http://en.wikipedia.org/wiki/The_Universe_%28TV_series%29
http://www.youtube.com/watch?v=iDkgAxx9MgY
EXCERPTS:
"Our Sun is one of billions of star in the milky way galaxy.
and our galaxy is one of hundreds of billions, may be a trillion in the known universe.
The Sombrero Galaxy / M104
28 million light years away.
WHIRLPOOL GALAXY / M51
CENTAURUS A
"a galaxy sending out massive amounts of radio waves."
HUBBLE ULTRA DEEP FIELD IMAGE
(an image of galaxies in the universe)
ANDROMEDA / M31
2 million light years
CANIS MAJOR DWARF GALAXY
small, hard to detect
"Now Canis Major Dwarf Galaxy is taking aim at the Milky Way.
Two galaxies on a collision course from which, thanks to gravity,
there is no escape."
"We think the Milky Way is a barred spiral galaxy
reaching about 100 thousand light years across
with a 3000 ligh year thick core.
Most galaxies in the Universe are smaller.
The milky way, and may alien galaxies, are are like cities,
with a central dense core and less dense suburbs.
All the stars in our galaxy are orbiting around the center.
We are about 30 thousand light years away from the center.
and it takes us about 250 million years.
to make one orbit around the galaxy.
One of those galaxies may be responsible for Andromeda's double nucleus.
Two huge clumps of stars found at its center.
Andromeda, 2.5 million light years away.
"That makes it the furthest object in the universe
you can see with the naked eye.
a clash with the Andromeda galaxy is not only inevitable,
but will forever change the local galactic landscape.
"if you look at the Milky Way galaxy and the Andromeda galaxy,
they are actually approaching each outer at a fairly astounding rate,
several hundred kilometers every second.
In our common experience like an exploding bomb,
everything exploded away from a center.
Now, is there an empty center to our universe?
Are we on a sheel of galaxies flying away
from wherever the original explosion was?
NO. and that is the amazing thing.
So no matter which galaxy you're on,
you see the others moving away from you.
Our local group of galaxies is a small group
or a cluster of about 3 dozen galaxies.
our Milky Way and Andromeda are the two dominant galaxies.
Most of the galaxies in our local group are small dwarf galaxies.
LARGE AND SMALL MAGELLANIC CLOUD
(two wellknown dwarf galaxies)
(In every center of the galaxy is super massive black hole.)
"Sometimes black holes swallow entiere stars creating fierce explosions called gamma ray bursts.
"So, if the Universe is expanding what's driving it?
The only answer scientists can come up with for now
a mysterious dark energy.
THE JAMES WEBB SPACE TELESCOPE
is due to launch in 2013
designed to explore the infrared spectrum
like never before.
James Webb:
Firstly it's more powerful, it has a bigger mirror.
Secondly, it is actually working at slightly longer infrared wavelenghts.
What Hubble and Webb have in common
is the power to see beyond atmospheric turbulence
that prevents astronomers from getting picture perfect images
from 99% of the sky.
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