GALAXIES Pages

Galaxies Def: large scale groups of stars (approx. 100 billion) bound by gravitational attraction- rotates around a center Def: large scale groups of stars (approx. 100 billion) bound by gravitational attraction- rotates around a center Also contain nebulae, planets, dark matter (90%), space, etc.. Also contain nebulae, planets, dark matter (90%), space, etc..

Is the center of every galaxy a supermassive black hole?

Small Magellanic Cloud Nearest galaxy 150,000 ly

Andromeda (M31) A large galaxy neighbor A large galaxy neighbor 2,900,000 ly 2,900,000 ly

Milky Way Structure Structure Barred spiral galaxy Barred spiral galaxy About 100,000 light-years wide About 100,000 light-years wide Sun is 30,000 light- years from the center Sun is 30,000 light- years from the center Rotates every 200 million years around “galactic center” Rotates every 200 million years around “galactic center”

Milky Way

Face-on view of the Milk Way Galaxy

Edge-on view of the Milk Way Galaxy

Galaxy Song from Monty Python 4txo&feature=related&safety_mode=true& persist_safety_mode=1&safe=active 4txo&feature=related&safety_mode=true& persist_safety_mode=1&safe=active 4txo&feature=related&safety_mode=true& persist_safety_mode=1&safe=active 4txo&feature=related&safety_mode=true& persist_safety_mode=1&safe=active

Types of Galaxies

M105 NGC 3384

Elliptical galaxy 60% of all galaxies 60% of all galaxies Contain older stars Contain older stars small small

LMC Large Magellanic cloud

NCG 6946 Spiral galaxies 30% of all galaxies 30% of all galaxies Older in center; younger in arms Older in center; younger in arms

A barred spiral galaxy

Merger of two Spirals to form an Elliptical

Irregular galaxy 10% of all galaxies 10% of all galaxies Contain young stars Contain young stars

M104 (The Sombrero Galaxy)

Hubble’s Law Galaxies are receding at a speed proportional to their distance Galaxies are receding at a speed proportional to their distance Farther galaxies are moving faster than nearby galaxies Farther galaxies are moving faster than nearby galaxies

Raisin bread analogy of an expanding universe

What would cause this? EXPANDING UNIVERSE! EXPANDING UNIVERSE! Cosmological red shift- supports this Cosmological red shift- supports this

Local group Local Group Local Group Milky way and nearest galaxies Milky way and nearest galaxies Contains at least 28 galaxies Contains at least 28 galaxies

What pattern do galaxies form in the universe?

AMAZING FACT Our known Universe contains at least 1,000,000 billions ( Thats One Million, Billions) of other Galaxies...like our own Milky Way. There is no doubt that there are other vast Universes in existence on top of our Universe Our known Universe contains at least 1,000,000 billions ( Thats One Million, Billions) of other Galaxies...like our own Milky Way. There is no doubt that there are other vast Universes in existence on top of our Universe

What is your galactic address

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