the whole sky (long exposure photographs)

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the whole sky (long exposure photographs)
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same thing, but now at IR wavelengths (from
space).note disk, bulge, dusty interstellar
clouds. (color coded red2 micron, green1.5
micron , blue1 mic.)
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a dust grain is a dense opaque object
too.bottom 1-2 microns (near-infrared color
coded) top 100 microns (far-infrared
false color)
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zoom-in on central 1500 LY near-IR (1-2
microns)
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zoom-in more central 130 LY radio image
(VLA) false color (color indicates brightness
only) radio shows ionized gas (hot) note
the little yellow dot down in the red areathis
is Sgr A note also magnetic field lines running
perpendicular to galactic plane poloidal
magnetic fields
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zoom-in on central 1500 LY near-IR (1-2
microns)
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1-2 microns 1500 LY elliptical stellar orbits
in central (1/10) LY
zoom-in on central 1500 LY near-IR (1-2
microns)
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central 200 LY radio image (VLA)
plus magnetic field map from far-IR polarimetry
SPARO (N.U. camera) can the combined effects
of poloidal and toroidal magnetic fields
be exploited to reveal polarity of field?
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An external galaxy a spiral like our own.
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An external galaxy a spiral like our own.
Which way does it rotate?
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An external galaxy a spiral like our own.
How does it rotate? i.e. what is rotation curve?
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An external galaxy a spiral like our own.
How does it rotate? i.e. what is rotation curve?
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An external galaxy a spiral like our own.
How does it rotate? i.e. what is rotation curve?
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An external galaxy a spiral like our own.
How does it rotate? i.e. what is rotation curve?
WRONG
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An external galaxy a spiral like our own.
How does it rotate? i.e. what is rotation curve?
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An external galaxy a spiral like our own.
How does it rotate? i.e. what is rotation curve?
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An external galaxy a spiral like our own.
How does it rotate? i.e. what is rotation curve?
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An external galaxy a spiral like our own.
How does it rotate? i.e. what is rotation curve?
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Vera Rubin beginning in the late 1960s she
began to study the rotation curves of nearby
galaxies
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an edge-on spiral its rotation curve can be
measured via Doppler shift of spectral lines
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flat rotation curves extend well beyond the point
where the stellar mass starts to peter out