Galaxies & Quasars

Normal Galaxies - Hubble Classification
4 Types:

Spirals – classified by size of central bulge

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Ellipticals – classified by shape

Irregulars

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Some Properties of Normal Galaxies

How far away are galaxies?

Measuring the distance to galaxies

Measuring the distance to galaxies

Nearby structure – the Local Group

Large-scale expansion of universe :

Hubble Law

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- and even larger scale  structure

large scale structure in the universe

Active galaxies – Interacting/Colliding?

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Mergers

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Dark matter

Gravitational Lensing ® Dark Matter

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