Transcript Lesson 1- Space

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