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Transcript
Year 9
Space;
the final frontier.
Today; 4th June
• Lesson 1; The Solar
System.
Postbox
1. What are the names of the planets in
our solar system?
2. What is a gas giant?
3. What is a comet?
4. What is an asteroid?
5. What is our nearest star?
Postbox
6. What is an eclipse?
7. Why does the moon change
shape?
8. What is the solstice?
9. Why do the seasons change?
10. What is a telescope?
The solar system
• There are 8 planets and one dwarf planet
in our solar system.
• Mercury, Venus, Earth, Mars, Jupiter,
Saturn, Uranus, Neptune and Pluto.
• Each planet orbits the Sun, which doesn’t
move.
Remember.
•
•
•
•
•
•
•
•
•
My
Very
Energetic
Mother
Jumps
Swiftly
Up
Netball
Poles
The Sun
The sun is a star that lives at the center
of the Solar System. Its huge gravity
holds the planets in place.
It is made of plasma (the 4th state of
matter) which gives out photons as
nuclear fission occurs.
Hydrogen becomes helium, which becomes
lithium etc. With each fission energy is
released.
• The energy that is given out is heat and
light energies.
• Our sun is both a medium sized and
medium temperature star.
• Our star still enough hydrogen to keep
under going fission for millions of years
before it becomes a supernova.
The Sun
The sun is a star that lives at the centre of the Solar System. Its huge gravity
holds the planets in place.
The planets
The planets all revolve around the Sun. There are nine in
total - Mercury, Venus, Earth, Mars, Jupiter, Saturn,
Uranus, Neptune and Pluto.
Moons
Moons rotate around their parent planet. Earth has one
moon, but some planets have over 30. Only Mercury and
Venus do not have any moons.
Mercury
Surface Type
Rocky
Temp. oC
300
Type of Atmosphere
None
Moons
0
Rings
No
Venus
Surface Type
Rocky surface covered
by thick clouds of
sulfuric acid
Temp. oC
400
Type of Atmosphere
Mainly Carbon dioxide
Moons
0
Rings
No
Earth
Mars
Surface Type
Rocks and water
Temp. oC
20
Type of Atmosphere
Air, containing oxygen,
nitrogen etc.
Moons
1
Rings
No
Surface Type
Red rocks
Temp. oC
-20
Type of Atmosphere
Thin atmosphere of
carbon dioxide
Moons
2 Phobos & Deimos
Rings
No
Jupiter
Surface Type
No solid surface
Temp. oC
-100
Type of Atmosphere
Hydrogen & Helium
Moons
16
Rings
3
Surface Type
No solid surface
Temp. oC
-150
Type of Atmosphere
Hydrogen & Helium
Moons
62
Rings
9 (made of ice and rock)
Uranus
Saturn
Surface Type
No solid surface
Temp. oC
-150
Type of Atmosphere
Hydrogen & Helium
Moons
27
Rings
13
Neptune
Surface Type
No solid surface
Temp. oC
-170
Type of Atmosphere
Hydrogen & Helium
Moons
13
Rings
3
Pluto
Surface Type
Rocky, covered in ice
Temp. oC
-180
Type of Atmosphere
Very thin atmosphere
of methane
Moons
1
Rings
No
Asteroids
Asteroids are rocky bits of debris up to 1,000km (620
miles) across. Most live in the asteroid belt between
Mars and Jupiter. They are the remnants from early
planets that collided and were torn apart.
Comets
Comets are dirty snowballs of ice and dust
that revolve around the Sun in long orbits.
When they approach the Sun their dark
surface absorbs sunlight and they heat up,
causing the ice beneath it to evaporate. The
gas and dust escape leaving a trail of gas
behind them, which looks like a tail.
Recent comets to fly-by the Sun include
Halley, Hale-Bopp and Ikeya-Zhang.
Meteor showers
Meteor showers are caused by debris
from a comet burning up in our
atmosphere
This produces spectacular shooting
stars which blaze across the night sky
The Planets
Use the table below to answer questions 1 and 2.
Planet
Statistic
Mercury
Venus
Earth
Mars
Jupiter
Saturn
Uranus
Neptune
Pluto
Average
distance from
Sun
(Million km)
57
110
150
220
770
1400
2800
4500
5900
Length of year
(Earth days)
88
225
365
687
4380
10585
30660
60225
90520
Diameter
(Thousand km)
5
12
13
7
140
120
47
45
6
Length of day
(Earth time)
59
days
243
days
1 day
1
day
10
hours
10
hours
11
hours
16
hours
6 days
Surface
temperature
(oC)
300
400
20
-20
-100
-150
-150
-170
-180
Gravitational
force on
surface (Nkg-1)
4
9
10
4
26
12
10
14
?
Questions:
1. Name the following:
a) The hottest planet?
b) The smallest planet?
c) The largest planet?
Venus
Mercury
Jupiter
d) The planet that it would be hardest to jump on?
Jupiter
2. It takes 1 year (365 days) for the Earth to make a complete journey around
the sun. How many Earth years does Jupiter take to make a complete journey
around the sun?
(4380 / 365 = 12 Earth Years)
3. Mercury is much closer to the sun than Venus, but Venus is hotter than
Mercury. Why?
Venus’s atmosphere is mainly carbon dioxide. This traps the Sun’s heat
(by the Greenhouse effect) making it hotter than Mercury.
4. Write two differences between a planet and a star.
1. Planets orbit the sun
2. Planets don’t have their own light source
Galaxies
Our sun is just one of 100,000 million stars that make up the Milky Way galaxy. If
it was possible to look at the Milky Way from above, you would see that our Sun is
located on an arm of this spiral galaxy.
There are at least 20 galaxies relatively closely grouped with the Milky Way, the
nearest of which is the Andromeda galaxy. Even so it is still an enormous distance
away – over 2 million light years! Beyond this group of galaxies there are billions
more, each containing millions more stars.
The
Milky
Way
Messier 81
NGC 3256
•
http://www.windows.ucar.edu/tour/link=/our_solar_system/moons_table.html
Diamond core!?!
•
The universe's biggest showoff
actually used to be a star, and
sometimes the debris that's left
over after the star dies starts a
second career as a planet. In
this case, Blingworld started off
life as one of two parts of a
binary star. The larger twin
supernova-ed. What was left
behind was a pulsar, and a
white dwarf. The
dwarf stabilized just far enough
away from its former brother to
lose matter to the bully but to
keep its carbon core.
Today; 9th June
• Lesson 3; The atmosphere & global
warming.
Life on Earth? Thanks atmosphere!
Today;
• Lesson 5; Celestial rotations.
The Earth’s rotation.
• The Earth makes a rotation around its axis
every 24 hours.
• The Earth takes 364.25 days to make one
rotation around the sun.
• The moon takes 28 days to orbit the Earth.
• But what does this all mean??
•
http://www.classzone.com/books/earth_science/terc/content/visualizations/es0408/es0408page01.cfm?chapter_no
=04
24 hours: 1 day
• The time it takes for the Earth to do one
rotations about its axis is a day.
• Which ever side is facing the Sun- day.
• The other side- night.
364.25 days: 1 year
• The time it takes for the Earth to complete
one orbit of the Sun, is one year.
Seasons
• As the Earth is on a 23.5o tilt different
parts of the Earth are closer to the Sun at
different points in the orbit.
• Glue in handout.
Summer
Summer
Summer
Winter
Winter
Rise
Winter
Set
Horizon
The Sun stays lower in Winter, so the day’s
are shorter.
Solstice
• The solstice is when
the point on the
Earth where you
are, is furthest or
closet to the Sun,
during the orbit.
• This happens in
summer and winter.
Equinox
• Halfway in between
the solstices, the
Earth is neither tilted
directly towards nor
directly away from
the Sun.
• This happens in
spring and autumn.
Phases of the moon
Phases of the Moon.
• http://en.wikipedia.org/wiki/Image:Lunar_li
bration_with_phase_Oct_2007.gif
• Moon match up activity.
Tides and the Moon.
• The gravitational force of the Moon and
Sun pulls at the whole earth. This
attraction causes the water in the oceans
and lakes to move slowly up and down
causing tides.
• Even though the Earth is being pulled on
one side, the water of the oceans bulge
out on both sides because of the
difference in the Moon’s gravity on the
surface of the Earth. Tides also vary
during a month.
Spring and Neap tides.
• Spring Tides: 2-3 days after a new or full
moon. Caused by the sun pulling in the
same direction as the Moon, High tides
are higher and low tides are lower.
• Neap Tides: just after the quarter moons.
Caused by the sun pulling at right angles
to the moon. The tides are less high and
less low than spring tides.
Summary
• Day and night- how it happens & how
long.
• Seasons- how do they happen?
• Equinox & solstice- what are they?
• Moon & tides- how does that work?
Today
• Lesson 6; The Sun, other stars and their
constellations.
The Sun is a star like the others that we see at night. The Sun
is not burning like a fire – it is a huge controlled hydrogen bomb.
The core is at a temperature of 14 million oC, and a very high
pressure. The hydrogen atoms are broken into pieces, which
smash into each other at high speed. This can make the pieces
of hydrogen atoms join together to become helium. This also
produces gamma radiation, which travels outward and heat and
light is radiated into space in all directions.
In the fusion process, some of the hydrogen’s
mass is turned into energy. At least 4 million
tonnes of hydrogen are used up every second on
the Sun. (It has such a large mass that it will last
for about another 5 billion years).
Life cycle of stars
Stars come in a variety of sizes. The brightest are 100 000 times brighter than our
sun and the dimmest 100 000 times less bright.
To measure the distances between stars it
is useful to use a unit which is very large.
We use the distance travelled by light in a
certain time. This is known as a light year.
The closest star to us is 4.2 light
years away and the furthest
discovered stars are 10 billion
light years away.
Stars are actually very faint lights
because they are far away. During
the day we can not see them as the
Sun is so powerful.
Even at night, the lights from cities
and towns make it difficult to see
them.
Constellations
• A constellation is a group of stars that
are connected together to form a figure or
picture. The term is also traditionally and
less formally used to mean any group of
stars visibly related to each other, if they
are considered as a fixed configuration or
pattern in a particular culture.
Orion: the hunter
Pledies: the 7 sisters
Crux: the southern cross
Scorpio: the scorpion
Taurus: the bull
Sagittarius: the archer
Constellations- Summary
navigate
constellations
fixed
sources
light years
Sun
sailors
Move
light
Southern Cross
Sun
sources
Stars like the ___________ are _______________ of light. This means that
light
they create their own ______________
energy. The distance between stars is
Light years
measured in __________________.
Stars have ____________________
positions in the sky. People imagine stars
fixed
constellations
create patterns in the sky, which are called _____________________.
From
move
Earth, stars appear to _____________________
in circles at night. This is
because the Earth is turning.
Southern Cross
The stars always seen above us make up the ______________________.
You can
sailors
use this to find the South Celestial Pole. It can be used by __________________
navigate
to ________________
their journeys.
Activity
• Create a star map to use at night.
Finding the South Celestial Pole (SCP)
Look to the south to find the Southern Cross and the bright
Pointer stars. Use the diagram below to find the SCP.
Another method used to find the SCP is to extend the long
axis of the Southern Cross by 4½ cross lengths.
Distant Stars.
The brightest star in the Southern Constellation of
Centaurus is called Alpha Centauri. Apart from the
Sun, it is the nearest bright star to us. It is 40
million million km away (4 light years). Other stars
are thousands of times further away.
The constellations we see are not near each other in
space. We see them together because they lie in the
same direction in space from our viewpoint.
e.g. Orion
Parallax Shift
Astronomers use this principle to measure the
distance to nearby stars. They note how a star
shifts position against the background of distant
stars when viewed from opposite ends of the Earth’s
orbit around the Sun.
Today;
• Lesson 7; Matakriki.
Matariki.
• The Maori New Year.
• Watch the DVD, to explore what Matariki
means to Maori.
• 27 mins.
Legends
• Matariki literally means the ‘eyes of god’ (mata
ariki) or ‘little eyes’ (mata riki). Some say that
when Ranginui, the sky father, and
Papatūānuku, the earth mother were separated
by their offspring, the god of the winds,
Tāwhirimātea, became angry, tearing out his
eyes and hurling them into the heavens. Others
say Matariki is the mother surrounded by her six
daughters, Tupu-ā-nuku, Tupu-ā-rangi, Waitī,
Waitā, Waipuna-ā-rangi and Ururangi. One
account explains that Matariki and her daughters
appear to assist the sun, Te Rā, whose winter
journey from the north has left him weakened.
Why is Matariki important?
• Traditionally, depending on the visibility of
Matariki, the coming season's crop was
thought to be determined. The brighter the
stars indicated the warmer the season
would be and thus a more productive crop.
It was also seen as an important time for
family to gather and reflect on the past and
the future.
Today;
• Lesson 8; Eclipses & NASA.
Solar eclipses.
• Solar eclipses occur when the Sun, Moon
and Earth line up, so the Sun is blocked
out by the Moon.
Lunar eclipse.
• Lunar eclipses occur when the Moon
passes through the Earth's shadow.
Since prehistoric times, people have looked at
the starts in the sky. For thousands of years
people have been able to see the bright points
of light in the sky they called stars.
William and Caroline Herschel.
William Herschel (1738 – 1822) and his
sister Caroline( 1750 – 1848) were
originally from Germany but spent much of
their time living in Bath, in England. William
was a professional musician, but began
making his own telescopes as his interest in
astronomy grew. He discovered the planet
Uranus in 1781. His work on the nature of
nebulae (enormous clouds of stars like our
own galaxy) and the structure of the
universe made him the first man to give a
reasonably correct picture of the shape of
our star-system which he called the galaxy.
Caroline was his devoted assistant and
herself discovered eight comets and
published many important findings.
History of Telescopes
Astronomy is the study of planets and stars, their movements within the Universe and what
they are made up of. Some of the planets and stars can be seen on a clear night using the
naked eye; indeed the planets Mercury, Venus, Mars Jupiter and Saturn have been observed
since ancient times.
Today, more detailed images are available thanks to the invention of telescopes. People could
see the craters on the moon and other planets in our Solar System. Modern telescopes
provide close-up images of stars and galaxies billions of kilometers away in space. Most
modern telescopes use a series of huge mirrors to reflect the light from the stars. These
telescopes are known as refractor telescopes.
One of the first telescopes was built by Galileo in 1609 and he used it in 1610 to explore the
mysteries of the Solar System. For the first time, the telescope enabled him to see the
moons around Jupiter.
In 1672, Isaac Newton developed the first reflecting telescope which used curved mirrors
rather than lenses to focus light from the stars. William Herschel (1738-1822) was
interested in astronomy and although he originally trained to be an organist, he built a giant
telescope at his home in Bath, England. In 1781, he discovered an unknown planet, which he
wanted to name after King George III of England, but it was later known as Uranus.
Today there is the unmanned Hubble Space Telescope, which orbits Earth and sends detailed
images of planets and stars back to Earth. This telescope allows us to look at other solar
systems which are too far away to be seen from the surface of Earth. We also have large
radio telescopes, the largest of which is the VLA (very large array) in Arizona, USA. Radio
telescopes look at the Universe using radio waves which give us information about things like
the formation of the universe and deep space objects that cannot be seen using other
telescopes.
1. What is astronomy the study of?
Astronomy is the study of planets and stars, their movements within the Universe
and what they are made up of.
2. Which planets in our Solar System been observed without the use of telescopes
since ancient times?
Mercury, Venus, Mars, Jupiter and Saturn have all been observed since ancient
times.
3. What is the name of the type of telescope which uses mirrors to reflect light
from the stars?
The type of telescope that uses mirrors to reflect light from the starts is known
as a reflecting telescopes.
4. How did the invention of the telescope change ideas about the solar system and
the Universe?
The telescope provided access to undiscovered areas of the Solar System and
Universe, enabling new starts and planets to be identified.
5. Name one of the first scientists to use a telescope to observe the stars and
planets. When did this scientist live?
William Herschel (1738 – 1822)
6. What did William Herschel discover about the Solar System?
William Herschel discovered Uranus
7. What is the Hubble Telescope? Explain how it is different to the telescopes
used by Galileo and Herschel.
An unmanned telescope in space orbiting the Earth, obtaining detailed pictures of
other planets, asteroids and stars in the Solar System.
8. Name the other modern type of telescope we use today and explain how is it
useful.
The other modern telescope is the radio telescope, which looks at the Universe
using radio waves which give us information about things like the formation of the
universe and deep space objects.
9. Explain why Galileo’s time people thought only our own Solar System existed.
Because people were unable to see beyond our Solar System using the technology
available at the time.
Telescopes
The astronomical refracting telescope
A simple refracting telescope contains 2 lenses:
1. An objective lens which has a long focal length
2. An eye lens which has a short focal length
The final image is inverted
(but astronomers are used to
this). To see very faint stars
the first lens must be as
wide as possible, to collect as
much light as possible.
Hubble telescope; 1990  ?
Mars
Saturn
Cat’s eye
nebula
Crab nebula
Supernova
• v
Nebula
Galaxy
Supernova
Reflecting telescopes
The reflecting telescope (invented by Sir Isaac
Newton) has a large concave mirror to collect the
light and to converge it towards a small plane
mirror.
The plane mirror reflects the light sideways to an
eye lens. This acts as a magnifying glass.
Radio Telescopes.
Radio telescopes look at the Universe using radio waves. They give us information
about things like the formation of the universe and deep space objects that cannot
be seen using other telescopes. Most radio telescopes take the form of a huge dish
that reflects and focuses incoming radio signals onto an aerial mounted above it.
The signals are fed to a receiver, where they are amplified and processed.
The Arecibo radio telescope in
Puerto Rico has a dish 305m
across and the Very Large Array
at Socorro, New Mexico, uses 27
dishes working together to
produce an effective dish 27km
across.
Diagram of a telescope
Light rays from the stars
Tube
Second curved mirror
Third flat mirror
Projected
image
First mirror
You can make a telescope by using two lenses as shown in the diagram.
Look through the lenses, and move
the thin lens along the ruler until
you see a sharp image.
Today;
• Lesson 9; Rockets.
Rockets are blasted into space due to the action
of the gas rushing out of the rocket, which
causes the rocket to react in the other
direction. The rocket goes in the opposite
direction to the gas, and the faster the gas
leaves the rocket, the faster the rocket gets
pushed the other way.
If the rocket is blasted at a
speed of more than 8km/s (25
times the speed of light), it
would still try to fall towards
the Earth, but because of the
curving of the Earth, the
rocket would stay at the same
height above the ground and
orbit the Earth.
Making a rocket.
• Use the kit provided and a large soft drink
bottle to create and launch your rocket!
• Rocket which travels the biggest distance
down the wire wins!
Today;
• Lesson 10; Meteors and Asteroids.
Mete-what?
• A meteoroid is a sand- to boulder-sized
particle of debris in the Solar System.
• The visible path of a meteoroid that enters
Earth's atmosphere is called a meteor, or
commonly a shooting star or falling star.
If a meteoroid reaches the ground, it is
then called a meteorite.
• Many meteors are part of a meteor
shower.
Asteroids
• Asteroids, sometimes called minor
planets or planetoids, are small Solar
System bodies in orbit around the Sun,
especially in the inner Solar System; they
are smaller than planets but larger than
meteoroids.
Words!
• A meteoroid is a sand- to boulder-sized
particle of debris in the Solar System.
• A meteor is a debris travelling through
Earth's atmosphere.
• If a meteoroid reaches the ground, it is
then called a meteorite.
• Asteroids, are small bodies in orbit
around the Sun, within the Solar system.
Impact craters.
K-T boundary
What happened?
• 65.5mya a massive meteorite hit Earth off
the coast of the Yucatan peninsula, and
wiped out most of life on Earth!
There are over 1 million known asteroids. Most are very small, but some rocks a
kilometre in size do pass close to Earth. One hits us roughly every 100,000 years.
You are going to investigate how big the effects of an asteroid impact could be. You
can estimate how far the debris from the impact might travel and how big the
impact crater could be.
Key factors:
Asteroid speed – dropping the object from different heights gives it a
different speed on impact.
Asteroid mass - We could change the mass of the balls dropped.
Dependant variables:
Debris range –
this is the furthest distance any sand from the ‘planet
surface’ travels.
Crater size -
This is the diameter of the crater that the dropped
object makes.
Method:
1. Use the sand pit in the junior school.
2. Smooth over the surface so that the sand is even.
3. Drop the ‘asteroid’ into the sand.
4. Measure the size of the crater and the range of the debris
5. Record all your results in a table.
Results:
Height (m)
Speed (ms-1)
0.2
2.0
0.4
2.83
0.6
3.46
0.8
4.00
1.0
4.47
1.2
4.90
1.4
5.29
1.6
5.66
Crater size (cm)
Debris range (cm)
Height (m)
Speed (ms-1)
Crater width
(cm)
Crater depth (cm)
0.2
2.0
9
2
0.4
2.83
10
4
0.6
3.46
10
6
0.8
4.00
12
7
1.0
4.47
12
7.5
1.2
4.90
12
7.5
1.4
5.29
13
10
1.6
5.66
13
10
Graph:
Plot a graph of:
1. speed against crater size
2. speed against debris range
Conclusion:
Note down any patterns you can see in your results.
Extension:
1. Write down the debris range in metres for an ‘asteroid’ of 1cm
diameter, dropped from 0.8m (speed = 4 ms-1)
2. A real asteroid could be: 1km diameter (100,000 times bigger) travelling
at 4kms-1 (1000 times faster)
Assume debris range is proportional to asteroid diameter and speed, so:
Debris = ‘our value’ x 100,000,000
Calculate, using the formula above, the debris range of a real asteroid
i) in metres (m) and ii) in kilometres (km)
3. Write down parts of the world or countries that are within the debris
range.