Friday, April 1, 2011

1.34 Describe how the orbit of a comet differs from that of a planet

Basic information:
This is the Comet Lulin first discovered two years ago, unlike other objects in the solar system that circle sun anticlockwise the lulin circles clockwise. From earth the optical illusion of the comets tail being in front as it approaches can be seen.

http://www.telegraph.co.uk/science/space/4782335/Chance-to-see-Comet-Lulin.html

a. Comets are usually made from _________
b. Comets have highly elliptical _______  compared to planets
c. Comets usually travel _________ than ________
d. Comets usually have long _______ , made when the heat from the Sun melts then vaporises the comet

Wednesday, March 30, 2011

1.32 Explain the effects of gravitational forces

1. The Moon orbits the Earth because of the ___________ / __________ between them
2. The Earth attracts the Moon and the Moon attracts the Earth with an _______ but _______ force
3. This is an example of Newton's ________ law
4.  Planets orbit the Sun because of the ___________ / __________ between the __________ and the __________
5. Artificial satellites orbit the Earth because of the ___________ / __________ between the __________ and the __________
6. Comets orbit the Sun because of the ___________ / __________ between the __________ and the __________
7. If the  ___________ / __________ were removed these objects would fly away at a t_________ to the orbit path

Monday, March 28, 2011

1.30 recall that the moon orbits the earth and that some planets also have other moons

http://www.universetoday.com/20489/moon-compared-to-earth/

How was the moon formed?


One theory of how the moon was formed is that it was formed from the debris ejected by an impact of a hugh object about 4.53 billion years ago when a molten earth was still cooling down. It was thought that earth was has a companion planet around it called Theia.  As Theia started having an ecentric orbit leading to its inelestic collision with earth at a very oblique angle.As the two planets collided with each other they stuck together this lead to a generation of an internse amount of heat which then led to a sinking and melting of Theia's iron core into earths core sending a significant amount of Theia's and Earths crust as well as mantle into a orbit around them.  

www.buzzle.com/articles/how-was-the-moon-formed.html
http://www.youtube.com/watch?v=M_YZIDhe7A8

How old is the moon?
Rocks that were brought back from the moon containing zircon crystals. The oldest zircons from the moon are about 10 million years older than the oldest yet discovered on earth. The ages of Lunar zircons identified in other studies hint that small amounts of the moons crust remained molten for another 200 million to 400million years.

http://www.sciencebuzz.org/blog/how-old-moon

Why does the moon only show one side to us all of the time?
This is because the dark side or far side of the moon is permanetly rotated away from our planet this particular phenomena is due to the speed the moon at which the moon rotates.

http://www.moonconnection.com/moon-same-side.phtml



Explain what will eventually happen to it?
The further the moon moves away from the earths gravitational field strength starts to decrease and the earths rotation will get slower. This will result in the longer days shorter nights and smaller tidal waves.

How much larger is the Sun than the Moon?
The sun is approximetly 400 times larger then the moon
What natural phenomenon does this ratio help to observe?
This ratio allows us to observe the natural phenomena of a solar eclipse which is when the moon passes in front of the sun.

How far away is the Moon?
The moon is approximetly on average 384,400Km (238,900 miles)

What was significant about the 19th March 2011 (regarding the Moon)?
On the 19th March astronomers predicted that a 'supermoon' would pass by earth at a distance of 356,577 Km this is the closest pass in 18 years. Astronomers refer to this as a Lunar Perigee.
Why is there no atmosphere on the Moon?
This is beacuse the moon compared to the earth is smaller and the gravitational force on the moons surface is weaker than the earths.


Why is the gravity on the Moon 1/6th than of Earth?
The weight on the moon is a function of the moons gravity. We must first understand that gravity is a force which attracts physical objects towards each other so it might be right to come to the conclusion that the larger the mass of the object the more gravitation force you will get. The moon is 1/4 the size of the earth so its gravity is much less then the earths.

How many people have stepped on the Moon? Who was the last?
About 12 people have walked on the moon. Here is a list of the 12 Neil Armstrong, Buzz Aldrin, Pete Conrad , Alan Bein, Alan Sheperd, Edger Mitchell, David Scott, James Irwin, John W. Young, Charles Duke, Eugene Cernan and the last person to step on the moon was Harrison Schmitt.

Why does the Moon orbit the Earth? How many days does it take to  orbit the earth and What effect does the moon have on earth?
It takes about 27.3 days for the moon to orbit the earth. The moons gradient intensity is responsible for the tidal behaviour on earth. It is also responsible for the eclipses when the moon, sun and earth are all in a strait line.

Moons of other planets:
How many moons are there in our solar system?
Their are about 26 moon in our solar system


The moon is slowly drifting away from us, bu how much per year?
The moon is moving away from the earth by 1 and a half inches per year away from earth

 1.31 understand gravitational ficld strength. g, and recall that it is different on other planets and the moon from that on the Earth.

Questions
Answers
What does small 'g' stand for in the equation W = mg?
 gravitational field strength
What is approximate value of 'g' on Earth?
10
What is approximate value of 'g' on the Moon?
0
What are the units for 'g'?
N/kg
Why is this equation useful?
This equation is useful becuase allows us to differentiate between mass and gravitational field stregth
Why is 'g' different on different planets?
Different mass
Which object in our solar system has the largest 'g'?
The sun
Explain why this object has the largest 'g'
The biggest mass
Where on a planet is 'g' the greatest?
In the center
What happens to the value of 'g' as you go further away from a planet?
It decreases
How does this affect your weight?
Decreases
Find your mass on the bathroom scales and then find your weight on different planets (click this link: http://www.exploratorium.edu/ronh/weight/), take a screen shot and upload the image to your blog