Revolutionary Thought

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Revolutionary Thought
Photo by Jan Wojcik
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Orbits?
Movement?
Spin?
Structure
Vibration?
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But what lies beyond?
Everything is moving away from the center and
other objects.
With the exception of the Andromeda Galaxy, the
universe seems quite content to leave us alone.
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What is the structure of the space around us?

• We know about the solar system
• We know about the Milky Way

Or do we?
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Inside the Milky Way
We know its pretty flat with a rounded center
100,000 l.y. across and only 1,500 l.y. thick
Most of the stars we see at night are actual very
near us, relatively, within our own galaxy.
There is a giant black hole at the center of the
galaxy
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The black hole at the core is approximately the
mass of 2.6 MILLION Suns
The entire galaxy rotates around it
It is only about 26,000 l.y. from Earth
Or, at least, thats what they think
http//news.bbc.co.uk/1/hi/sci/tech/934033.stm
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So thats it, right?

• We know what were made of
• We know how we move
• We know whats around us
• Its a miracle we dont get sucked into the black
  hole
  
• But now all we have to do is come up with a
  general field theory, right?

Not Exactly
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Our galaxy is eating one of its neighbors!
The Magellanic Clouds are not the only galaxies
near our own.
There is an old, dwarf galaxy orbiting us, and
our mass is tearing it apart!
http//skyandtelescope.com http//news.bbc.co.uk/
2/hi/science/nature/3142582.stm

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The old stars are type M giants, emitting
mostly infrared light.
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Interestingly, the orbit doesnt wobble
(precession) This means that the mass of the gal
axy must be nearly spherical!
The galaxy does have a halo of old, burned out
white dwarf stars that probably helped form the
galaxy as we know it.
A new study shows that this halo may account for
up to 35 of the dark matter necessary
http//news.bbc.co.uk/1/hi/sci/tech/1236460.stm
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The orbital plane of these stars lies very close
to our position in the Milky Ways arm.
That means that some of these stars may/have
end(ed) up in our solar neighborhood!!
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What is the Solar Neighborhood?
100,000 light years
With our Sun in the middle, the neighborhood is a
mere 20 light years across
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THE SKY IS FALLING!
The Red Giants are coming!
But it doesnt necessarily mean that were going
to get a great celestial showMaybe we can
convince the University to buy an infrared
converting telescope thingy
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Ok, so how do they claim to know all this?
Two Micron All Sky Survey really big, infrared
telescopes being used to map the sky
By using infrared, Astronomers can see through
the dust of the Milky way and create a mapping of
all the stars in the sky, so to speak. Combined
with distance data, they can produce a 3-D plot
of the universe, at least as far as light
intensity and red shift allows.
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COOL, HUH?
Questions?