Leesa Harvey
Web Quest
Grade 6
Topic: Science
Astronomy
In this first website you will be
watching a video about the history of our solar system and how we have come to
know what we know about the solar system around us including the different
sections. http://www.youtube.com/watch?v=SmyMQ_SdpNc&feature=related(ONLY
LISTEN TILL THE LADY STOPS TALKING)
While watching this video answer
the following questions.
- What were the five closest planets to earth thought to
be before they
were classified for planets?
- Before about 400 years ago what did astronomers think
was the center of
the universe?
- Why did astronomers only know of the closest five planets?
- Who was the first to recognize that the sun was at the center of the solar system?
- How many moons did Galileo see around Jupiter, and how does that support the sun being the center of the solar system?
For this website you will be
exploring the planets.
First click on the picture of the
solar system.
Read “An Introduction” and “The
solar system is made up of two parts:”
and answer the following questions.
- How do the planets travel around the sun? What is this called?
- What are the two parts of the solar system and what planets are in
them? What is the thing that separates these two
parts?
Next click on the rocket to
continue your exploration and answer the following questions
- What is the difference between rocky planets and gas planets?
- What are the rocky planets?
- _______________ , _____________ , _____________ , ______________ ,
________________
(dwarf planet)
- What are the gas planets?
- ________________ , ______________ , _____________ , _______________
- What are the size limits of small planets and giant planets?
- Which planets are considered small planets?
- ______________ , ______________ , _____________ , _____________ ,
_______________ (Dwarf Planet)
- Which planets are considered giant planets?
- _____________ , ______________ , ______________ , ______________
Next click on the planet to explore
the planets more.
Choose which planet you what to
find out more about and click on it.
Then draw the planets symbol and
share once interesting fact from the page.
On this website you will be
studying the moons in our solar system.
First see how many moons are on the planets (Look at the right under the
purple heading) and write how many moons are orbiting each planet. (Do not count the provisional moons)
Earth_____________
Mars_____________
Jupiter____________
Saturn____________
Uranus____________
Neptune___________
Now make a bar graph of the number
of moons orbiting each planet.
http://www.youtube.com/watch?v=gVtGUTEzo6A&feature=related Listen to the YouTube video. It is of Neil
Armstrong as he is landing on the moon.
Share one thing you heard that you
did not realize was part of the first walk on the moon.
What do you think will be next in
our exploration of space?
(Use this question only if it is a
breaking point)
In this website you will be able to compare the size of
different things in our universe.
Pay attention to the page that comes up because it shows you
how you will navigate the website.
Once you understand the instructions click on “Start” to
continue.
Next scroll through the different sizes and example in our
universe and answer the following questions.
- What are the three things shown in the smallest circle, titled 0.0000000001 yoctometers? Have you heard about these three things before?
Next find each of the planets. List their size in kilometers and meters and
one fact you learned.
Earth
51,000 km
5.1 X 10^7 m
DO NOT LOOK UP THIS PLANET (I MIGHT JUST LEAVE THIS ONE OUT)
Now order the planets from Largest to Smallest
______________ , _____________
, ______________ ,
_______________ ,
______________ , _____________
, ______________ ,
_______________
What was your favorite thing to see
on this website?
On this next website
you will be trying to figure out the reasons different forms of asteroids will
hit a planet or other object in Space.
1) Move your mouse over the words “What’s your
angle?”, “Step on it!”, “Pick a comet - any comet!”, “It’s a matter of mass…”,
and “Target practice” Read the descriptions that will be appear on Jupiter when
you highlight the words. These tell you
what you will be working on in each section.
2) You may choose the order in which you work on
the sections, but “Target practice” must
be last. When you choose a section
to work on, find it in the list below and answer the question(s). Warning: you may look at scoop, but DO NOT
just write the answers from scoop they must be in your own words to receive
credit.
a. “What’s your angle?”
What is the relationship between distance from the planet and the force
of gravity?
b. “Step on it!”
How does the speed of the comet affect its
path?
c. “Pick a comet – any comet!”
What is the relationship between the mass of the comet and its
acceleration?
Read in “scoop” at the bottom of the page to find out about the math
behind Acceleration. First click “scoop”
and then click “GET ANSWER”. Explain in
your own words what you read.
d. “It’s a matter of mass…”
What is the relationship between the mass of
the celestial object and the gravitational force it exerts on the comet?
Once you have finished all the Activities to learn about how distance,
speed, mass, acceleration, and gravitational force click on the “Target
practice” link. In this you try to hit
or miss Jupiter by altering the asteroids angle and speed. Try to both hit and miss. Below tell me the angle and speed you used to
either hit or miss Jupiter, and how many time it took you to accomplish this
goal.
HIT
Angle_________
Speed___________
How many tries________
MISS
Angle___________
Speed____________
How many tries__________
Now that you have figured out how distance,
speed, mass, acceleration, and gravitational force affect asteroids share your
results from the game with you neighbor.
For the next website you will be exploring the history of the
telescope. http://amazing-space.stsci.edu/resources/explorations/groundup/
Click on the Era that you fill
would most interest you. Read the
information on the era you chose and then write a summary of what you learned.
(If you do not like the era you first choose click on “EXPLORE ERAS” in the top
left corner to choose another one)
After your summary look up least 2 different pictures of telescopes
that come from the era you studied.
Paste in this document and copy the URL you found it on. Under the
pictures label; the name, date the telescope was made, and who it was invented
by.
In this website there is a list of
the 10 closest stars. http://www.sciencekids.co.nz/sciencefacts/topten/closeststars.html
Answer the following question.
- How you heard of any of these stars before? If so which ones and what have you heard about them?
Next click on the word “Sun”, look
at the information and choose 3 facts you find that interest you.
1)
2)
3)
http://www.lpi.usra.edu/education/skytellers/solar_system/activities/ss_string.shtml On this website we are doing the activity of
making a “Solar System on a String” mobile.
Read what the activity will be
like.
Look to the right of the screen at the
“What’s Needed?” list, grab everything from the counter that you need to make
your mobile.
Next look at the “Solar System I’m
Rhyme” below and start putting together your mobile.
The Solar System I’m Rhyme
I’m the one star in this special place.
You’ll find me in the center.
Just guess my name to start this game,
then you may surely enter……
I orbit fast, but s l
o w l y turn,
With a 1,416 hour day!
I’m the first. My name is __________________,
I’m small and I am gray.
Because my ghastly atmosphere is mainly CO2,
It’s like a scorching greenhouse of 900 degrees. It’s true!
My name is _______________, I’m yellow and the hottest,
And all I can say is, “Whew!”
I’m glad I’m home to boys and girls,
Even though I do seem “blue”,
I’m Planet_______________.
and a little larger than Venus (that’s your clue!)
I’m reddish-rust, with rocks and dust
And a 24-hour day.
I’m _____________ and I am close in size
To Mercury, I’d say!
I’m a band that’s full of rocks and dust
That travel in between
The Inner and Outer Solar System’s planetary scene.
And because I’m a band of asteroids, I felt,
I should be called The ________________ __________.
I’m full of gas, with colorful stripes,
And a really enormous girth.
I am mighty ______________ and
I’m over ten times the size of Earth!
I’m yellow and my ammonia haze
covers each and every thing.
I’m _____________and my beauty’s
found within my icy rings!
I’m blue and stinky (it’s methane gas!).
I have more than twenty moons!
I’m______________, the third gas giant;
A bit larger than neighbor Neptune.
It takes me over sixty thousand days
to go one whole year through!
I’m the last gas giant. I’m old ___________,
and just a little darker blue.
I’m the smallest chunk of icy rock,
but a planet, I will not doubt!
I’m ____________, and even though I’m least,
Oh, please don’t kick me out!
For the last website you will be
taking a quiz on this website http://kids.discovery.com/quizzes/space/our-planets.
When you answer each question there will be information on the bottom of the
page use that information to answer the questions on this page. Also at the end record your score out of ten.
1)
Where else do you see iron oxide or rust?
2)
Look up and explain in your own words the difference
between Orbiters and Surveyors.
3)
Do you think the moon reflect the sun light just like
this planet?
4)
Why do you think this element is necessary for survival
of living things?
5)
If Uranus, Jupiter, Neptune, and Saturn all have rings
how many planets don’t have rings?
6)
Have you learned anything else about this planet while
working on this assignment, and explain?
7)
What was one thing you learned about gravity from the
asteroid website?
8)
What was the funnest thing you found out about the
telescope era you read about on the other website?
9)
Do you know any other ANSWER Gods? If so who and what were they over?
10) Make
up your own sentence to remember the order of the planets.
Score ________
/ 10
This is a website with more links
to interesting solar system websites if you wanted to go further. http://mrscienceut.net/SolarSystem.html
Leesa Harvey
Web Quest
Grade 6
Topic: Science Astronomy
In this first website you will be
watching a video about the history of our solar system and how we have come to
know what we know about the solar system around us including the different
sections. http://www.youtube.com/watch?v=SmyMQ_SdpNc&feature=related (ONLY LISTEN TILL THE LADY STOPS TALKING)
While watching this video answer
the following questions.
- What were the five closest planets to earth thought to
be before they
were classified for planets?
They were thought to be moving lights
- Before about 400 years ago what did astronomers think
was the center of
the universe?
The Earth
- Why did astronomers only know of the closest five planets?
They are visible to the naked eye without
the use of a telescope
- Who was the first to recognize that the sun was at the center of the solar system?
Nicolaus Copernicus
- How many moons did Galileo see around Jupiter, and how does that support the sun being the center of the solar system?
Four, and then answers will very, but should reflect gravity.
For this website you will be exploring
the planets.
First click on the picture of the
solar system.
Read “An Introduction” and “The
solar system is made up of two parts:”
and answer the following questions.
- How do the planets travel around the sun? What is this called?
The planets travel in circular paths called orbits around the sun in a
counter-clockwise direction.
- What are the two parts of the solar system and what planets are in
them? What is the thing that separates these two
parts?
There is the inner solar system (Mercury, Venus, Earth, and Mars)
and outer solar system (Jupiter,
Saturn, Uranus, Neptune, and Pluto)
and the asteroid belt separates the two.
Next click on the rocket to
continue your exploration and answer the following questions
- What is the difference between rocky planets and gas planets?
Rocky planets are made of rock and metal, are very heavy, move slowly,
and do not have rings and very few have moons.
Gas planets are made mostly of gases (hydrogen and helium), they are
light, move quickly, have rings, and lots of moons.
- What are the rocky planets?
- _Mercury_ , _Venus_ , _Earth_ , _Mars_ , _Pluto_ (dwarf planet)
- What are the gas planets?
- __Jupiter__ , _Saturn_ , _Uranus_ , _Neptune_
- What are the size limits of small planets and giant planets?
The small planets have diameters less than 13000 km, and giant planets
have diameters greater than 48000 km.
- Which planets are considered small planets?
- _Mercury_ , _Venus_ , _Earth_ , _Mars_ , _Pluto_ (Dwarf Planet)
- Which planets are considered giant planets?
- _Jupiter_ , _Saturn_ , _Uranus_ , _Neptune_
Next click on the planet to explore
the planets more.
Choose which planet you what to
find out more about and click on it.
Then write the planets name and
draw its symbol and share once interesting fact from the page.
Planet’s Name
Picture of Planet’s Symbol
One interesting fact on the planet
(May
very from student to student)
On this website you will be
studying the moons in our solar system.
First see how many moons are on the planets (Look at the right under the
purple heading) and write how many moons are orbiting each planet. (Do not count the provisional moons)
Earth____ONE____
Mars___TWO___
Jupiter__FIFTY__
Saturn__FIFTY-TWO__
Uranus_TWENTY-SIX__
Neptune_SIXTEEN_
Now make a bar graph of the number
of moons orbiting each planet.
(this will most likely be drawn)
http://www.youtube.com/watch?v=gVtGUTEzo6A&feature=related Listen to the YouTube video. It is of Neil
Armstrong as he is landing on the moon.
Share one thing you heard that you
did not realize was part of the first walk on the moon.
This answer will very from student to student, but should be related to
the film.
What do you think will be next in
our exploration of space?
This answer will very from student to student.
In this website you will be able to compare the size of
different things in our universe.
Pay attention to the page that comes up because it shows you
how you will navigate the website.
Once you understand the instructions click on “Start” to
continue.
Next scroll through the different sizes and example in our
universe and answer the following questions.
- What are the three things shown in the smallest circle, titled 0.0000000001 yoctometers? Have you heard about these three things before?
Planck Length, String, Quantum Foam The second part of the question will vary
depending
on the student.
Next find each of the planets. List their size in kilometers and meters and
one fact you learned.
4,900 km
4.9 x 10^6 m
Mercury is the closest planet to the
sun. It has no atmosphere. During the day, temperatures reach 400° C,
but at night, the tempuratures fall to -180° C.
One Mercurian year is 88 Earth days.
12,000 km
1.2 x 10^7 m
There was a time when Venus and Earth were
thought to be sister planets. That isn’t
true at all! Venus’s surface temperature
is always above 450° C, because its atmosphere, which is mostly carbon dioxide,
traps the Sun’s heat!
12,700 km
1.27 x 10^7 m
The Earth is our only home. While living on it, we may consider it huge,
but it is still important to take care of it.
When it is gone, there will be nowhere else left to go.
Earth
6,800 km
6.8 x 10^6 m
Mars is known as the Red Planet. It is red because it is rusty. Many people believe water and life once
existed on Mars. However, even if that
is true, the life wouldn’t be like the little green men.
140,000 km
1.4 x 10^8 m
Jupiter is the largest planet in the solar
system. However, it is not the largest
known planet. That’s TReS-4. Jupiter is a gas giant, so it’s just a ball
of gas. You can’t land anywhere on
it. Also, Jupiter has 64 moons,
including four Gallilean moons.
120,000 km
1.2 x 10^8 m
Saturn has the widest, most visible rings
of the solar system. Galileo, who was
the first person to see these
rings, first thought they were “ears”. Can you imagine a Saturn without rings? It would be just a yellow ball.
51,000 km 5.1 X 10^7 m
DO NOT LOOK UP THIS PLANET (I MIGHT JUST LEAVE THIS ONE OUT)
49,000 km
4.9 x 10^7 m
Currently, Neptune
is the farthest planet in the solar system from the sun. It takes 164.8 Earth years for it to orbit the
Sun. You’ll never see Neptune
complete a single orbit in your whole life, unless life expectancies increase.
Now order the planets from Largest to Smallest
__Mercury__ , _Mars_
, __Venus__ , __Earth__ ,
__Neptune__ , __Uranus__ , _Saturn_ , __Jupiter__
What was your favorite thing to see
on this website?
Answers will very depending on the students
On this next website you will be trying to figure out the reasons
different forms of asteroids will hit a planet or other object in Space.
1) Move your
mouse over the words “What’s your angle?”, “Step on it!”, “Pick a comet - any
comet!”, “It’s a matter of mass…”, and “Target practice” Read the descriptions
that will be appear on Jupiter when you highlight the words. These tell you what you will be working on in
each section.
2) You may
choose the order in which you work on the sections, but “Target practice” must be last.
When you choose a section to work on, find it in the list below and
answer the question(s). Warning:
you may look at scoop, but DO NOT just write the answers from scoop they must
be in your own words to receive credit.
a. “What’s your
angle?”
What is the relationship between
distance from the planet and the force of gravity?
The comet launcher is far
enough away that the angle at which the comet is launched is changing the
distance between the comet and Jupiter. The change in the comet's path is
caused by Jupiter's gravity, which is providing an unbalanced force. This
unbalanced gravitational force increases as the distance between Jupiter and
the comet decreases. When the comet is fired at 90°, it is far enough away from
Jupiter that there is no unbalanced force acting on the comet so its path is
unchanged. As the angle decreases, the comet comes closer to Jupiter and thus
experiences a greater and greater unbalanced gravitational force, until at 0°
the comet's path is changed so much that it hits the planet.
b. “Step on it!”
How does the
speed of the comet affect its path?
As
the speed of the comet increases, the energy associated with its motion
increases and if the energy is high enough the comet will be able to escape
Jupiter's gravitational force. In the vicinity of Jupiter, Jupiter's
gravitational field primarily determines the motion of the comet. The comet
"falls" toward Jupiter because of Jupiter's gravity, just like on
Earth. Objects fall toward the planet's surface with constant acceleration due
to the unbalanced gravitational force of the planet. The faster the comet is
going initially, the farther it will go before it hits Jupiter. If it's going
fast enough, it won't hit Jupiter, but will go into orbit instead. At the
fastest speeds, it will escape Jupiter's gravity completely.
c. “Pick a comet
– any comet!”
What is the relationship between the
mass of the comet and its acceleration?
The mass of the comet
doesn't matter because its acceleration (how quickly it will change its speed
or direction) depends only on how near it is to a planet and the mass of the
planet. This is similar to objects falling on Earth: they fall at the same rate
regardless of their mass (as long as air resistance is minimal)
Read in “scoop” at the bottom of the
page to find out about the math behind Acceleration. First click “scoop” and then click “GET
ANSWER”. Explain in your own words what
you read.
To calculate the
acceleration, a, of a body, divide the force, F, applied to the body by the
mass, m, of the body: a = F/m. In the case of the comets, the force applied
depends on the mass of the comet, the mass of the planet, and the distance
between the two. When the mass of the comet is divided by the mass of the
comet, it factors to one so the mass of the comet doesn't affect its
acceleration near the planet. Since we are keeping the mass of the planet and
the distance from the planet (expressed as the angle) constant, the
accelerations of all comets are the same and they follow the exact same path.
d. “It’s a
matter of mass…”
What is the
relationship between the mass of the celestial object and the gravitational
force it exerts on the comet?
According to Newton's Law
of Gravitation, as the mass of one body increases, its ability to exert a
gravitational force on the other body also increases: the larger the mass, the
greater the gravitational force. The asteroid didn't have much mass, so, at
this distance, the unbalanced gravitational force was small and the asteroid
was unable to influence the path of the comet. Earth's mass was great enough to
exert a small unbalanced gravitational force on the comet. This force changed
the path of the comet but was not large enough to actually capture the comet.
Massive Jupiter not only captured the comet but, exerted such a large
unbalanced gravitational force that the comet impacted the planet.
Once you have finished all the
Activities to learn about how distance, speed, mass, acceleration, and
gravitational force click on the “Target practice” link. In this you try to hit or miss Jupiter by
altering the asteroids angle and speed.
Try to both hit and miss. Below
tell me the angle and speed you used to either hit or miss Jupiter, and how
many time it took you to accomplish this goal.
HIT
Angle__30_
Speed_Slowest_
How many
tries_#_
MISS
Angle_30,60,90_
Speed_Any accept when 30 cannot be slowest
How many
tries_#_
Now that you
have figured out how distance, speed, mass, acceleration, and gravitational
force affect asteroids share your results from the game with you neighbor.
For the next website you will be
exploring the history of the telescope. http://amazing-space.stsci.edu/resources/explorations/groundup/
Click on the Era that you fill would most
interest you. Read the information on
the era you chose and then write a summary of what you learned. (If you do not
like the era you first choose click on “EXPLORE ERAS” in the top left corner to
choose another one)
Summary of the Era they chose
After your summary look up least 2 different pictures of telescopes
that come from the era you studied.
Paste in this document and copy the URL you found it on. Under the
pictures label; the name, date the telescope was made, and who it was invented
by.
Picture Picture
Name name
Date made date
made
Who invented who
invented
In this website there is a list of
the 10 closest stars. http://www.sciencekids.co.nz/sciencefacts/topten/closeststars.html
Answer the following question.
- How you heard of any of these stars before? If so which ones and what have you heard about them?
Answers will very depending on the student
Next click on the word “Sun”, look
at the information and choose 3 facts you find that interest you.
·
The Sun is a star found
at the center of the Solar System.
·
It makes up around
99.86% of the Solar System’s mass.
·
At around
1,392,000 kilometres (865,000 miles) wide, the Sun’s diameter is
about 110 times wider than Earth’s.
·
Around 74% of the Sun’s
mass is made up of hydrogen. Helium makes up around 24% while heavier elements
such as oxygen, carbon, iron and neon make up the remaining percentage.
·
Light from the Sun
reaches Earth in around 8 minutes.
·
The Sun’s surface
temperature is around 5500 degrees Celsius (9941 degrees Fahrenheit), so pack
plenty of sunscreen if you plan on visiting (remembering that the average
distance from the Sun to the Earth is around 150 million kilometers).
·
The Sun’s core is around
13600000 degrees Celsius!
·
The Sun generates huge
amounts of energy by combining hydrogen nuclei into helium. This process is
called nuclear fusion.
·
Because of the Sun’s
huge influence on Earth, many early cultures saw the Sun as a deity or god. For
example, Ancient Egyptians had a sun god called Ra while in Aztec mythology
there is a sun god named Tonatiuh.
·
The Sun produces a solar
wind which contains charged particles such as electrons and protons. They
escape the Sun’s intense gravity because of their high kinetic energy and the
high temperature of the Sun’s corona (a type of plasma atmosphere that extends
into space).
·
Planets with strong
magnetic fields such as Earth manage to deflect most of these charged particles
as they approach.
·
A solar eclipse occurs
when the Moon is between the Sun and the Earth.
http://www.lpi.usra.edu/education/skytellers/solar_system/activities/ss_string.shtml On this website we are doing the activity of
making a “Solar System on a String” mobile.
Read what the activity will be
like.
Look to the right of the screen at
the “What’s Needed?” list, grab everything from the counter that you need to
make your mobile.
Next look at the “Solar System I’m
Rhyme” below and start putting together your mobile.
The Solar System I’m Rhyme
I’m the one star in this special place.
You’ll find me in the center.
Just guess my name to start this game,
then you may surely enter……
I orbit fast, but s l
o w l y turn,
With a 1,416 hour day!
I’m the first. My name is __Mercury__,
I’m small and I am gray.
Because my ghastly atmosphere is mainly CO2,
It’s like a scorching greenhouse of 900 degrees. It’s true!
My name is _Venus_,
I’m yellow and the hottest,
And all I can say is, “Whew!”
I’m glad I’m home to boys and girls,
Even though I do seem “blue”,
I’m Planet_Earth_.
and a little larger than Venus (that’s your clue!)
I’m reddish-rust, with rocks and dust
And a 24-hour day.
I’m _Mars_
and I am close in size
To Mercury, I’d say!
I’m a band that’s full of rocks and dust
That travel in between
The Inner and Outer Solar System’s planetary scene.
And because I’m a band of asteroids, I felt,
I should be called The _Astroid
Belt_.
I’m full of gas, with colorful stripes,
And a really enormous girth.
I am mighty _Jupiter_
and
I’m over ten times the size of Earth!
I’m yellow and my ammonia haze
covers each and every thing.
I’m _Saturn_and
my beauty’s
found within my icy rings!
I’m blue and stinky (it’s methane gas!).
I have more than twenty moons!
I’m_Uranus_,
the third gas giant;
A bit larger than neighbor Neptune .
It takes me over sixty thousand days
to go one whole year through!
I’m the last gas giant. I’m old _Neptune_,
and just a little darker blue.
I’m the smallest chunk of icy rock,
but a planet, I will not doubt!
I’m _Pluto_,
and even though I’m least,
Oh, please don’t kick me out!
(Also they will have a mobile when done)
For the last website you will be
taking a quiz on this website http://kids.discovery.com/quizzes/space/our-planets.
When you answer each question there will be information on the bottom of the page
use that information to answer the questions on this page. Also at the end record your score out of ten.
1)
Where else do you see iron oxide or rust?
Answers will very, but may be like rust on metal as it has gotten
old, and wet
2)
Look up and explain in your own words the difference
between Orbiters and Surveyors.
Answers will very, but orbiters travel around and orbit to view the
planet, and surveyors are on the planet collecting samples and surveying the
terrain and things on the planet.
3)
Do you think the moon reflects the sun’s light just
like this planet?
Answers will very, but yes the moon does reflect the sun’s light and
that is why we can see it.
4)
Why do you think this element is necessary for survival
of living things?
Answers will very, but they need to know we need water to survive.
5)
If Uranus, Jupiter, Neptune, and Saturn all have rings
how many planets don’t have rings (not including Pluto)?
Four
6)
Have you learned anything else about this planet while
working on this assignment, and explain?
Answers will very, but should focus on what they have learned about
Earth.
7)
What was one thing you learned about gravity from the
asteroid website?
Answers will very, but should be talking about Gravity.
8)
What was the most interesting thing you found out about
the telescope era you read about on the other website?
Answers will very, but should focus on the telescopes.
9) Do you know any other ANSWER
Gods? If so who and what were they over?
Answers will very, but should focus on Ancient Roman Gods.
10) Make up your
own sentence to remember the order of the planets.
Sentences will very, but should be in this order M_________ V__________
E___________ M_________ J___________ S____________ U___________ N____________
Score __#__ / 10
This is a website with more links
to interesting solar system websites if you wanted to go further. http://mrscienceut.net/SolarSystem.html
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