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A walk through the Universe

Space is big. You just won’t believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it’s a long way down the road to the chemist’s, but that's just peanuts to space. Douglas Adams,

The Hitchhiker's Guide to the GalaxyEnglish humorist & science fiction novelist (1952 - 2001)

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The Earth We are here

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EARTH

Mercury

Venus

Mars

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Earth

Saturn

UranusNeptune

Jupiter

Pluto (not a planet) and its moon Charon

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The Sun

is our nearest star

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The Solar System

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The Milky Way (Our Galaxy)

A hundred, thousand, million stars!

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the Milky Way as seen from the Enterprise

A hundred thousand light years across

Light would take 100 000 years to travel across the galaxy.

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Distances It takes 8 minutes for light to reach

us from the Sun. A light-year is the distance travelled by

light in 1 year.

The Sun is our nearest star. Our next nearest star, Alpha

Centauri is 4 light years away.

The Milky Way is 100 000 light years across.

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The local group of galaxiesAndromeda is the nearest biggalaxy to theMilky Way

Milky Way

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Light from Andromeda takes 2 million years to reach us.

Milky Way

Andromeda

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Local grou

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The Local SuperclusterHere the local group has shrunk to the size

of the Milky Way in the last slide.

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It left when the dinosaurs were on Earth.

Light from Virgo has taken 65 million years to reach us.

Virgo Cluster

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The Universe is mind-bogglingly big!

The Sun is about 150 000 000 km away from Earth

Bright stars in the night sky are about 1000 000 (1 million) times as far away as the Sun.

The near galaxies are about 100 000 times as far away as the bright stars. 15 000 000 000 000 000 000 km

18NASA