Grade Nine Science
Space Unit
• http://www.youtube.com/watch?v=SWOoV
4b49SI
What can we see in the sky?
• What are some things that we can see in the
sky?
• Something that people have noticed and
documented throughout time is that there
are patterns in what we see in the sky.
• Constellations
• North Star
• Moons
• Planets
• The study of what is beyond Earth is called
Astronomy.
Star Constellations
• Groups of stars that seem to form shapes
and patterns are called constellations.
• Some stars look as though they are close
together when some are really much farther
from Earth than others.
• Constellations have been used for thousands
of years as calendars, timekeepers and
direction finders for travellers.
Constellations
• http://www.youtube.com/watch?v=uKXBt
WHExwQ
• The solar system consists of our sun and all
the objects that travel around it.
• Planets and moons are nonluminous. They
do not emit their own light. We can see
them in the sky only when the light from the
Sun reflects off them towards Earth.
• Only 5 of the planets in our solar system
can actually be seen with an unaided eye:
Venus, Mars, Jupiter, Saturn and Mercury.
How big is the universe
• http://www.youtube.com/watch?v=Zr7wNQ
w12l8
What is the difference between
Stars and Planets?
Feature
Planet
Star
Location :
In the solar system
Far beyond the solar
system.
Distance from Earth:
Fairly near
Very far
Real Size:
Smaller than most stars
Usually larger than planets
Reason why we see
object:
Reflects light from the sun Emits its own lights.
Surface Temperature:
Usually cool or very cold
Very hot
What is the object made
of:
Usually rocks or gases.
Gases under high pressure
and temperature.
Long-term observable
feature
Very slowly wanders
through constellations
Appears to move through
sky as part of a
constellation.
What sound does the Earth make
• http://www.youtube.com/watch?v=5AVHX
MLDvWA&feature=related
Sound of the Sun
• http://www.youtube.com/watch?v=pGwDd
TZBAEY&feature=related
The Sun: An Important Star
• The sun provides us with the energy needed
by all plants and animals on Earth
• It’s gravitational pull keeps us in our steady
orbit.
• Because the Sun is the closest star to Earth,
it is the brightest object in the sky. It gives
off so much light energy that you cannot see
the other stars until the Sun has set.
• The Sun’s energy comes from a process
called Nuclear Fusion.
• Nuclear Fusion occurs because inside the
Sun the temperature and pressure are so
high that substances fuse (join together) to
form new substances.
• In this process, large amounts of heat, light
and other forms of energy that travel out
from the Sun through Space.
• Every second the Sun makes more energy
than humans have used throughout our
entire history.
• Scientists have predicted that the Sun has
been producing energy for 5 billion years
and predict that the Sun will continue
producing energy for about another 5 billion
years.
Parts of the Sun
• Core – where nuclear fusion produces the
Sun’s energy (temp of 15 million degrees C
and enormous pressure)
• Radiative Zone – first layer that surrounds
the core. Energy may take a million years to
reach the next zone.
• Convective Zone – hotter substances rise as
colder substances fall. Energy moves
outward to the photosphere.
Parts of the Sun
• Photosphere – surface of the Sun (avg. temp
of 5500 degrees C) and Sun Spots occur
here.
• Chromosphere – the inner atmosphere of
the Sun (60,000 degrees hotter than
photosphere).
• Corona – thin outer layer of the solar
atmosphere – gleaming white, halo-like –
that extends millions of km into space.
Parts of the Sun
• Sun Spots – dark spots appearing on the
surface that are cooler than the area
surrounding them.
• Solar Flare – gases and charged particles
expelled above an active sunspot.
• Solar Prominence – low energy gas
eruptions from the Sun’s surface that extend
thousands of km into space.
Aurora Borealis/Aurora Australis
• Solar flares emit charged particles, which
travel much slower than light.
• When these particles reach Earth they are
focused by the Earth’s magnetic field, at the
north and south poles.
• These charged particles produce the
Northern Lights and Southern Lights.
Characteristics of Stars
• The color of stars tell us something about
their temperature.
• A relatively cool star glows red.
• A very hot one glows a bluish-white or even
blue.
Characteristics of Stars - Colour
Colour
Blue
Temperature Range
Example(s)
(degrees C)
25 000 – 50 000
Zeta Orionis
Bluish-White
11000 – 25 000
Rigel, Spica
White
7500 – 11 000
Vega, Sirius
Yellowish-White
6000 – 7500
Polaris, Procyon
Yellow
5000 – 6000
Sun, Alpha Centauri
Orange
3500 – 5000
Arcturus, Aldebaran
Red
2000 – 3500
Betelgeuse, Antares
Characteristics of Stars
• Stars the size of the Sun or smaller are
called Giants.
• Stars with masses 10 times or more larger
than the Sun’s become Supergiants.
• A star the size of the Sun or smaller is said
to have “died” when the nuclear reactions
die down, the core shrinks and the outer
layers of the star drift away. This becomes a
dwarf star.
• Dwarf stars are stars with a higher
temperature than red or yellow stars.
Characteristics of Stars
• Stars are also classified by their brightness.
• There are six categories, with the brightest
stars called first magnitude and the faintest
stars called sixth magnitude stars.
• Apparent Magnitude – how bright a star
appears to you.
• Absolute Magnitude – actual amount of
light given off .
Stars
• A spectroscope is an instrument used by
astronomers to look at the light given off by
the Sun and other stars.
• This device splits light into a pattern of
colors so we can see them as separate lines
of color.
• It can also tell what chemical elements
make up a star, how much of each element
each star contains, the temperature of a star
and the direction the star is moving.
The Life of a Star
• Stars follow a predictable series of stages:
they are born, they develop and die.
• Gravity is the force that pulls objects
towards each other. The more mass that an
object has, the more gravity it exerts.
The Sun has stronger gravity than Earth.
The force gets smaller as the distance
between objects increases.
How do Stars form?
• All stars begin their lives in nebulas.
• Nebulas are huge clouds of dust and gases,
mainly hydrogen and helium.
• Dust and gases swirl around, breaking into
clumps and contracting because of
gravitational forces.
• As the dust and gasses swirl around they
become bigger and their gravitational force
becomes stronger.
How do Stars form?
• More particles begin to pack together and
eventually the clumps are dense and hot
enough for nuclear fission to start.
• No two stars are the same.
Supernovas
• A supernova is an enormous explosion that
occurs at the end of a large star’s life.
• By this stage the star has used up the fuels
needed to produce energy by the process of
nuclear fusion.
Death of a Star
• http://www.youtube.com/watch?v=vCMXV
8j2GtE
• http://www.youtube.com/watch?v=ysJ4Nj3
3rIo&feature=related
Neutron Stars
• When a star is about 10 times the mass of
the Sun dies, the resulting core is called a
neutron star. This star is composed of
neutrons.
• A Pulsar is a type of a neutron star that
emits pulses of very high radio waves.
• Pulsars are very small, about 20 km in
diameter and very dense with the mass of a
normal star.
Black Holes
• When a star about 30 times the mass of the
Sun dies, the resulting core is called a black
hole.
• A black hole is a small, very dense object
with a force of gravity so strong that
nothing can escape from it.
• Even light cannot be radiated away from its
surface.
How big is the Sun?
The Sun Compared to Other
Stars
How big is the sun
• http://www.youtube.com/watch?v=e5WnXI
3Ycs0
What is the Universe?
• What things do we consider to be in the
Universe?
The universe is everything that exists,
including all matter and energy everywhere.
The Solar System
• What planets make up our solar system?
• (In order from the sun) , Mercury, Venus,
Earth, Mars, Jupiter, Saturn, Uranus,
Neptune, and Pluto (dwarf planet).
• The planets revolve around the Sun in paths
called orbits.
• The orbits of most planets are nearly
circular, with the Sun at the center of each
orbit.
• The period of time for one revolution
around the sun is called one orbital period.
• The earth’s orbital period is about 365 days.
• The earth’s rotation around its axis once
every 24h causes our day and night cycle.
Earth’s Rotation
• The Earth rotates (spins) on an axis.
• It takes 24 hours to do one rotation around
its axis.
• This motion causes most stars, sun and
moon to appear to rise in the east and set in
the west.
• The Earth’s axis is an imaginary line that
connects the North Pole to the South Pole.
Earth’s Revolution
• The Earth’s Revolution is the motion of one
object travelling around another.
• It takes Earth one year to travel and revolve
in a circle around the sun.
• This allows us to see different stars and
constellations during different seasons.
• The angle of the Earth’s axis and the
Earth’s Revolution causes the different
seasons.
Seasons
• http://www.youtube.com/watch?v=WLRA8
7TKXLM&feature=related
• The order from biggest planet to smallest is
as follows.
• The largest planet is Jupiter. It is followed
by Saturn, Uranus, Neptune, Earth, Venus,
Mars, Mercury, and finally, tiny Pluto (a
dwarf planet). Jupiter is so big that all the
other planets could fit inside it.
The Inner vs. Outer Planets
• The inner planets (those planets that orbit
close to the sun) are different from the
Outer planets (those planets that orbit
farther from the sun).
• The inner planets are: Mercury, Venus,
Earth, and Mars. They are relatively small,
composed mostly of rock, and have few or
no moons.
• The outer planets include: Jupiter, Saturn,
Uranus, Neptune, and Pluto (a dwarf
planet). They are mostly huge, mostly
gaseous, ringed, and have many moons
(again, the exception is Pluto, the dwarf
planet, which is small, rocky, and has one
large moon plus two tiny ones).
• The planets of the solar system are made up
of different combinations of chemical
elements which is why no two planets are
the same.
• Scientists have determined that throughout
the solar system there are four common
elements: hydrogen, helium, oxygen and
carbon.
• These common elements are found under
high pressure on the Sun and on the four
largest planets.
Mercury
• Closest planet to the Sun.
• Recieves 10 times the amount of sunlight
than Earth giving it 400 degrees celsius
daytime temperatures.
• It has no atmosphere to trap heat so
nighttime temperatures fall to –180 degrees
celsius.
• Has craters all over planet.
Venus
• Has a thick atmosphere that can reflect
sunlight.
• Brightest planet in the sky.
• Second planet from the Sun.
• Atmosphere is mainly made of carbon
dioxide. This gas acts like the glass of a
greenhouse, keeping the surface
temperatures high enough to melt lead.
• Venus is hard to explore because of its thick
atmosphere.
Earth
• Third planet from the Sun.
• Atmosphere mainly contains nitrogen,
oxygen, and water vapour.
• There is also a small amount of ozone that
filters out some of the Sun’s radiation but
lets enough through for life on Earth.
• Water covers 70% of Earth.
Mars
• Fourth planet from the Sun.
• Called the Red Planet because of the
reddish color of its soil.
• Space Probe, Pathfinder, landed on Mars in
1997 and provided us with first hand photos
of the planet.
• Evidence that Mars once had volcanoes,
glaciers, and floods of water.
Jupiter
•
•
•
•
Fifth planet from the sun.
Largest of all planets.
11 times the diameter of Earth.
Has a giant red spot where huge hurricanes
form fed by constant high winds.
• Has 63 moons.
• Has orbiting rings of rock.
Saturn
• 6th planet from the sun
• Second largest planet.
• Atmosphere is cloudy because of its quick
rotation.
• Has over 1000 separate rings.
• Average temperature is – 180 degrees
Celsius.
Uranus
•
•
•
•
7th planet from the Sun.
4 times the size of Earth.
Rotates on its side.
Atmosphere is mainly made up of hydrogen
with some helium and methane.
• Has winds that blow up to 500 km/ h.
• Takes 84 years to complete one orbit.
Neptune
• 8th planet from the Sun.
• First planet to be located by mathematical
predictions.
• Orbits the Sun every 165 years.
• 4.5 billions km away from the Sun.
• Windiest planet 1000+ km/h
• Made mainly of ice
• http://www.youtube.com/watch?v=29wfzot
aBIg
Pluto
• The International Astronomical Union
(IAU) formally downgraded Pluto from an
official planet to a dwarf planet.
• According to the new rules a planet meets
three criteria: it must orbit the Sun, it must
be big enough for gravity to squash it into a
round ball, and it must have cleared other
things out of the way in its orbital
neighborhood.
• Pluto takes 248 years to orbit the Sun.
Planetary Moons
• Large natural objects that revolve around
planets are called satellites or moons.
• The moon we have orbiting Earth has no
atmosphere.
• 1610 Galileo was the first person to see four
of Jupiter’s moons.
Planet
Planetary
Number of known
moons
Moon
Count in 2008
Mercury
0
Venus
0
Earth
1
Mars
2
Jupiter
63
Saturn
60
Uranus
27
Neptune
13
Pluto
3
• http://www.windows.ucar.edu/tour/link=/ou
r_solar_system/moons_table.html
Asteroids
• rocky objects that travel throughout space.
• They are usually smaller than planets but
larger than meteorites.
• Between Mars and Jupiter there is ring of
asteroids called an asteroid belt.
• 1937 an asteroid named Hermes came
within 800,000 km of Earth.
• Asteroids are rich in minerals which
humans may have to mine someday.
Meteoroid
• A lump of rock or metal that is trapped by
the Earth’s gravity and pulled down through
the Earth’s atmosphere.
• As it falls it rubs against the molecules of
the air causing friction. This friction causes
the meteoroid to become hot and vaporize.
• This produces a bright streak across the sky.
• If the object is large enough to hit the
ground before totally vaporizing, it is called
a Meteorite.
Comets
• A comet is a chunk of frozen matter that
travels in a very long orbit around the Sun.
Distances in Space
• Distances in space are very large, so
scientific notation is used to abbreviate
these large measurements.
• Using this notation, a number is written
with a digit between 1 and 9 before the
decimal, followed by a power of 10.
How are Distances Measured
in Space?
• To measure long distances with as much
accuracy as possible, they use the largest
baselines available.
• One way that scientists measure distances in
space is to use the diameter of the Earth.
This method could be used to determine the
distance to the moon or a nearby planet.
• The largest baseline available is the
diameter of the Earth’s orbit. This is used to
help scientists calculate distances to the
stars nearest to our solar system.
• The distance from our Sun to the next
nearest star that you can see without a
telescope is about 4.1 x 1013 km. This star
is called Alpha Centauri.
• The light year is another measurement of
distance that scientists use.
• A light year is the distance that light travels
in one year.
• Light travels at about 300, 000 km / second.
• In one year it can travel 9.46 x 1012 . So the
distance to the nearest star is 4.3 light years
away.
Probes to the Planets
• A space probe is an unpiloted spacecraft
sent to explore parts of the solar system
beyond Earth.
• The probe collects information and
transmits it back to Earth.
Hubble Telescope
• Part 1
http://www.youtube.com/watch?v=SpkrVw_E
6Nw&feature=related
Part 2
http://www.youtube.com/watch?v=upXTZE5
7Z5U&feature=related
• Part 3
• http://www.youtube.com/watch?v=xt9Bvc8
s_d0&feature=related
• Part 4
• http://www.youtube.com/watch?v=1_9gsFc
Kh9I&feature=related
• Part 5
http://www.youtube.com/watch?v=gnCvHnlN
T7c&feature=related
Part 6
http://www.youtube.com/watch?v=PwkW76jR1w&feature=related
• Part 7
http://www.youtube.com/watch?v=fqYshfjc7U&feature=related
Part 8
http://www.youtube.com/watch?v=23MXsnp
C-5Y&feature=related
Pictures from the Hubble
• http://www.youtube.com/watch?v=_Fs8oIdD7o&feature=fvw
Hubble Deep Field
• http://www.youtube.com/watch?v=mcBVcXVWFw