A walk through the Universe

1. 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)

3. The Earth We are here

5. Venus Mercury Mars EARTH

7. Uranus Jupiter Neptune Earth Pluto (not a planet) and its moon Charon Saturn

8. The Sun is our nearest star

9. The Solar System

10. The Milky Way (Our Galaxy) A hundred, thousand, million stars!

11. the Milky Way as seen from the Enterprise Light would take 100 000 years to travel across the galaxy. A hundred thousand light years across

12. 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.

13. The local group of galaxies Andromeda is the nearest big galaxy to the Milky Way Milky Way

14. Light from Andromeda takes 2 million years to reach us. Milky Way Andromeda

15. The Local Supercluster Here the local group has shrunk to the size of the Milky Way in the last slide. Local group

16. Light from Virgo has taken 65 million years to reach us. Virgo Cluster It left when the dinosaurs were on Earth.

17. The Universe is mind-bogglingly big! • The Sun is about 150000000 km away from Earth • Bright stars in the night sky are about 1000000 (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

18. NASA