Download do not look directly at the sun without eye protection. if you do, you

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DO NOT LOOK DIRECTLY AT THE SUN
WITHOUT EYE PROTECTION.
IF YOU DO, YOU WILL DAMAGE YOUR
EYES FOREVER!
In this booklet we will discuss the transit of Venus, which is when the
planet Venus drifts across the face of the Sun as we see it.
At Sydney Observatory, we will use filters that block more than 99% of
the harmful infra red and ultra violet radiation.
Please ensure that everyone, especially children, only use the correct
filters to look at the Sun.
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It is possible to safely watch the transit yourself if you have a small telescope or a pair of binoculars. Use the telescope or the
binoculars to project the image, as shown in the image above. With your back to the Sun, aim the telescope towards it (this is not as
difficult to do as it sounds – use the shadow of the telescope) and focus its image onto a white card held about 200mm behind the
eyepiece. Venus will appear as a black spot with a width of 1/33rd of the Sun’s width and should be easily seen.
DO NOT LOOK THROUGH THE TELESCOPE OR BINOCULARS! Never leave the telescope unattended and ensure that children
are supervised at all times. Viewing the projected image is quite safe, but looking through the telescope or binoculars will cause
almost instant and irreversible blindness.
For a direct safe view of the Sun, a pair of Sydney Observatory eclipse glasses can be purchased for $5.00 each.
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Where will the 2012 transit of Venus be visible, and what about the weather?
Image courtesy of Fred Espanak, NASA
The transit of Venus occurs when the planet
Venus drifts across the face of the Sun as we
see it from Earth.
You have to be in just the right position to
see it and luckily here in Sydney, we will get
a great view if the sky is clear. Yes, of course
we are always worried about the weather!
In the space below, keep a record of the
weather for 6 June.
The temperature at _________ (time) today
is ______°C
(you will find a large thermometer in the Russell Room)
Image courtesy of the Bureau of Meteorology
Circle the picture above which best describes the weather today.
If it is cloudy, try to identify what type of cloud it is and draw a circle
around it.
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Transit animation
On the following pages, you will see several slightly
different images of the transit. Hold the book in the
centre at the top with your left hand and flip through the
pages quickly from the front to the back. (The booklet
needs to have been printed double-sided for this to
work.) You will see a simple animation of Venus drifting
across the Sun.
We have put north at the top.
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We now know
there are about
130 billion
galaxies in the
observable
Universe.
The Universe is
about 13.7
billion years
old.
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A single galaxy like the Milky Way may
have 200,000 million stars in it.
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There may be as many as
20,000 stars just like the
Sun in the Milky Way.
SUN FACTS
− 5 billion years old
− 1.4 million km diameter
− 5,500°C surface temperature
− 10 million°C core temperature
− Converts 4 million tonnes of
hydrogen into energy every
second
To see the latest videos and images of the Sun from space visit
http://www.nasa.gov/mission_pages/soho/
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(not drawn to scale)
The family of objects that travel around the star called
the Sun (or “Sol”) is known as the Solar System.
Our Solar System has one star, eight planets, nearly 200
moons, eight dwarf planets and millions of comets and
asteroids;
but do they just wander all over the place?
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Lots of things rotate.
This ice skater is rotating in
an anticlockwise direction.
If you can go to Sydney Observatory, look for the models
of the Solar System called orreries like the one shown
above.
Have you ever seen the hands of a clock
move? If you watch very carefully you will
see them move but quite slowly.
Then look for the planet models. Two spin clockwise and
one anticlockwise.
Put an arrowhead on the end of the curved
line to show which way the hands move.
This direction is called “clockwise”.
1. The planet ______________spins anticlockwise.
2. The planet ______________spins clockwise
3. The planet ______________spins clockwise
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Faster than a speeding …
It is sometimes difficult to understand how fast our
planets move.
Some racing cars can travel at
300km per hour which is about 80m
per second. That is nearly the length
of a football field every second!
Passenger jets are even faster!
They can travel at about 900km
per hour which is about 250m
per second.
Both racing cars and jets are slow
compared to the planets.
Mercury orbits the Sun every 88 days at
about 48km per second.
Venus orbits the Sun every 225
days at 35km per second.
Can you name the planets
on the dais in order?
Our Earth orbits the Sun every 365
days at a slightly slower 30km per
second.
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Many spacecraft have now been to Venus.
The first landing on Venus was Venera 3 on 1 March 1966.
It was from the former USSR but did not survive the incredible temperature
of up to 463°C and atmospheric pressure 92 times greater than on Earth.
Perhaps you can design your own spacecraft to survive
the hostile environment of Venus.
Sputnik 7
was the first
mission to
fly by Venus
in 1961
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As the planets orbit the Sun, sometimes they line up and
eclipse, transit or block one another’s view.
What happened to the Sun in the picture below? Where has
it gone? It looks like some of the Sun has been removed,
but it is really just the Moon moving between us and the
Sun, creating a shadow.
Image courtesy of
Fred Espanak
Did you know some
people thought eclipses
were caused by dragons
eating the Sun and
Moon!
Sometimes everyday objects or people line up
too and can make an unusual sight, like this!
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Here we can see a simplified diagram of
the Moon moving between the Earth and the Sun.
This is called a solar eclipse.
DO NOT LOOK DIRECTLY AT A SOLAR ECLIPSE!
(not drawn to scale)
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The Moon orbits the Earth every 29 days but it rarely
passes through the Earth’s shadow.
It does pass through the Earth’s shadow twice every three
years to cause a lunar eclipse. These are safe to look at
directly.
The next total lunar eclipses that can be seen from
Australia are:
1. 15 April 2014
2. 8 October 2014
3. 4 April 2015
4. 31 January 2018
This series of images was taken in December 2011.
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Only three large objects can
move between us and the Sun.
Choose which three objects
and draw a line from each one
to its correct position.
(not drawn to scale)
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(approximate scale as seen from Earth)
The three objects that pass between the Earth and the Sun
are:
1. The planet Mercury,
2. The planet Venus, and
3. The Moon.
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Venus is a very hot planet.
The atmosphere is so “heavy” or dense it would crush us instantly.
There is also a lot of volcanic activity.
It is not a nice place compared to Earth.
Draw a circle around the different features that you might find on Venus.
Draw a cross through the features you wouldn’t find on Venus
VENUS FACTS
− Second planet from the Sun
− Hottest planet in the Solar
System, with temperatures
reaching up to 463ºC
− Atmospheric pressure 92
times that on Earth
− A day on Venus is 243 Earth
days
− Only 650km smaller than
Earth
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Mercury moves between us and the Sun about
13 or 14 times per century, Venus four times
every 243 years and the Moon three times
every two years.
So why are we so interested in the rare transit
of Venus?
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In 1768 a famous voyage took the HMB Endeavour from England to Tahiti
to see the 1769 transit of Venus.
Who was the captain? ____________________________
The Astronomer Royal, Edmond
Halley, worked out how to
measure the size of the Solar
System.
The idea was simple but proved
difficult to do.
Astronomers had to carefully
observe the transit of Venus from
different locations. They had to
record the EXACT times of the
four contact points.
We’ll talk more about them soon.
At Sydney Observatory there is a model of the Endeavour.
Internet question: What other famous ship had the same name? S _ _ _ _ S _ _ _ _ _ _ Endeavour
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Captain James
Cook
1728-1779
Did you know the
cottage where
James Cook was
born was moved to
Melbourne’s Fitzroy
Gardens from
England in 1934?
We now know he took very good measurements of the four
contact times:
st
1 contact is when Venus first touches the edge of the Sun.
2nd contact is when Venus is first fully inside the Sun.
3rd contact is when Venus touches the edge before leaving the
Sun.
4th contact is the last touch of Venus on the edge of the Sun.
Modern examination of Cook’s data showed his error was just
1.5 seconds! Using his data, the distance from the Earth to the
Sun was between 149 and 151 million km. The current value is
149,598,000 km.
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What did Tahiti and the planet Uranus
have in common with King George III?
Fort Venus
At one time, both Tahiti
and the planet Uranus were
named after King George III,
but not any more.
Uranus, formerly
Georgium Sidus
Fort Venus, Tahiti, from Journal of a Voyage to the South Seas, Sydney Parkinson, 1784.
Dixson Library, State Library of New South Wales.
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The next transit of Venus after Cook’s voyage was in 1874. What
famous observatory was built just 16 years before, in 1858?
S _ _n _ _ O_ _ _r _ _ _ _ _ y
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Henry Chamberlain Russell,
Government Astronomer at
Sydney Observatory from
1870 to 1904.
At Sydney Observatory you can visit the 290mm telescope designed by H.C. Russell to watch
the 1874 transit of Venus. It is one of the few telescopes in the world to have seen the 1874,
2004 and 2012 transits (provided it is clear). It can be found in the south dome.
It is the o _ _ _ _ t working t _ _ _ s c _ _ e in Australia. (use all of these letters: esledletoc)
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Transit of Venus find-a-word
How many of the following words can you find
below?
transit
venus
telescope
captain
cook
planet
moon
clockwise
tahiti
observatory
solar
system
galaxy
universe
mercury
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Join the dots to see where three different
transits of Venus will have been seen (if it is
clear on 6 June 2012).
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Important dates of the transit of Venus
1631 Predicted by Johannes Kepler
1639 Jeremiah Horrocks saw the first predicted transit
1769 Captain James Cook went to Tahiti
1874 Sydney Observatory’s first transit
1882 It was cloudy everywhere and the transit couldn’t
be seen
2004 The first Internet broadcast of the transit
2012 _____________________________ saw the
transit at _____________________________
2117 The next one: it’s only 105 years to wait.
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Some images from previous transits
Henry Chamberlain Russell’s book
published in 1892
Make your own drawings here
of the 2012 transit.
Photograph by Geoffrey Wyatt of the
4 June 2004 transit of Venus
Amateur astronomer Mr Alfred Fairfax’s
drawing from December 1874
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Why is it important now?
In the past we used the transit of
Venus to work out the distance of the
Earth from the Sun.
Interestingly, the amount of light we
see from the Sun drops as Venus
transits. This can be measured very
accurately.
Astronomers now use this idea and
watch other stars. If a star’s light is
observed to dim, they can tell if an
exoplanet (a planet around a star
other than the Sun) is present.
It’s not easy!
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Record your key contact times here
(“Contact” refers to the four times when Venus is just touching the Sun’s outer or inner edge. They are very difficult to measure accurately.)
First contact 8:_ _ am.
This is when the planet Venus just appears to touch the Sun as we see it.
Second contact 8:_ _ am.
Third contact 2:_ _ pm.
This is when the planet Venus first appears fully inside the Sun as we see it.
This is when the planet Venus last appears fully inside the Sun as we see it.
Fourth contact 2:_ _ pm. This is when the planet Venus just appears to leave the Sun as we see it.
Make sure you visit www.sydneyobservatory.com/log-your-transit to enter your
contact time data. This will be used to work out the distance from the Earth to the
Sun. You will then receive a certificate of participation via email.
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Just to confuse everyone…
The flick animation to the right always
has “North” at the top but that is NOT
how we see it. The rotation of the round
Earth actually makes the Sun look like it
rotates too. If you were to mark the
transit every half hour or so, it would
follow a curved path!
First contact
8:16am
Fourth contact
2:44pm
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Autographs
We saw the 2012 transit of Venus
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Credits
Eclipse visibility courtesy of F. Espenak, NASA
Common types of cloud image courtesy of the
Bureau of Meteorology
Produced by Sydney Observatory staff 2012
See you for the
next transit in
© 2012 Trustees of the Museum of Applied Arts
and Sciences.
2 _ _ _,
maybe
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☺