Space…

…the final frontier

• “A book of knowledge is spread out before us in the pageant of the heavens, but we cannot turn the pages. All we can do is read the first word of the first sentence of the first chapter”

• “There are 100 billion galaxies with a billion trillion suns”

-Carl Sagan

Why do we know so little?

• Think about it:– BHS to the Mall = 1km– Bridgewater to Halifax = 100km– Halifax to Vancouver = 6000km

– Earth to moon = 38,000km– Earth to sun = 146 million km (minimum)– Earth to Mars = 56 to 400 million km (depending)

Travel to the Stars?

• Closest star outside the solar system is 40 trillion kms away.– Fastest spacecraft now= 100,000km/h

• That would take 50,000 years

– If we could get to 10 million km/h (1% light speed)• That would take 500 years

– If we could get to 100 million km/h (10% light speed)• That would take 50 years

• At light speed it would still take 5 Years. And that is to the CLOSEST star!

If the universe is so big how can we study it?

• Telescopes- Big ones, small ones….

• Probes- Scan with X-rays, microwaves and other forms of light. Take lots and lots of pictures

• Math and Logic- We can determine the distance and size of objects using observation and calculation

Why bother?• Why spend

billions of $$ on space research when people are starving here on Earth?

Reasons for space research

• Tells us more about our planet– The origins of life– How it was formed– Bird’s eye view of everything

• Gives us a better understanding of how everything works– Physics, geography, history, biology…

• We have 5 billion years to find a new planet, but it’s a BIG haystack and we’re not sure if the needle even exists!

Plus Space is just Awesome!

Our Solar System• Formed around the sun roughly 4.6 billion years

ago• 8 planets (Pluto’s not a planet)

– Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune

– My very educated mother just showed us nine planets.

• 146 moons• 1000s of asteroids• And a whole lotta nothin.

Understanding of the Solar System

• Ptolemy (Claudius Ptolemaeus) 2nd Century C.E.

Geocentric Universe:

• Earth is the centre of the Universe

• Earth doesn’t move and everything else goes around it

• Earth is round (well he was right about that!)

Nicolaus Copernicus- 1543

• Heliocentric Universe:

• The Sun is the centre of the universe

• Mercury, Venus, Earth, moon, Mars, Jupiter and Saturn circle the sun.

• The distance to the stars was vast (much further than the sun)

Galileo Galilei- 1564-1642

• Found the Copernican model was better than the Ptolemaic model at predicting events such as eclipses

• Used the ‘new fangled’ telescope to observe, Venus, Saturn and even the Milky way

• Disproved the Ptolemic model.

Current View of Universe

• There is no “centre”

• The solar system is just one of millions in the galaxy

• The galaxy is just one of millions in the universe

• In other words, we are very very very small