Mars facts learn all about mars

 

Gravity 

Read, then answer:

Gravity is the force by which a planet or other body draws objects toward its centre. The force of gravity keeps all of the planets in orbit around the sun.

1.  What keeps all of the planets in orbit around the sun? The force of Gravity around the world 

What else does gravity do?

Why do you land on the ground when you jump up instead of floating off into space? Why do things fall down when you throw them or drop them? The answer is gravity: an invisible force that pulls objects toward each other. Earth's gravity is what keeps you on the ground and what makes things fall.

2.  Define gravity in one sentence 

Why dose things land on the ground instead of floating Gravity makes things land on the ground and stay on the ground  

An animation of gravity at work. Albert Einstein described gravity as a curve in space that wraps around an object—such as a star or a planet. If another object is nearby, it is pulled into the curve. Image credit: NASA

Anything that has mass also has gravity. Objects with more mass have more gravity. Gravity also gets weaker with distance. So, the closer objects are to each other, the stronger their gravitational pull is.

3. What makes gravity weaker? objects that have gravity in it will make it float 

Earth's gravity comes from all its mass. All its mass makes a combined gravitational pull on all the mass in your body. That's what gives you weight. And if you were on a planet with less mass than Earth, you would weigh less than you do here.

4. What does Earth’s gravity come from? All of its mass 

5. Look at the image below and write how much you’d weigh on the following planets if you weighed 100lbs on Earth.

Jupiter 253lbs           Mars 38lbs      Venus 91lbs

Saturn  107lbs              Neptune 114lbs

6. How much would you weigh on the moon?  17lbs

Image credit: NASA

You exert the same gravitational force on Earth that it does on you. But because Earth is so much more massive than you, your force doesn’t really have an effect on our planet.

7. Why doesn’t your force really have much effect on Earth? It is so much more massive then on earth then mars 

Gravity in our universe

Gravity is what holds the planets in orbit around the sun and what keeps the moon in orbit around Earth. The gravitational pull of the moon pulls the seas towards it, causing the ocean tides. Gravity creates stars and planets by pulling together the material from which they are made.

8. What causes ocean tides? The gravitational pull of the moon towards the sea 

9.  How does gravity create stars and planets? By pulling the materials together 

Gravity not only pulls on mass but also on light. Albert Einstein discovered this principle. If you shine a flashlight upwards, the light will grow imperceptibly redder as gravity pulls it. You can't see the change with your eyes, but scientists can measure it.

Black holes pack so much mass into such a small volume that their gravity is strong enough to keep anything, even light, from escaping.

10. Why is gravity in black holes so strong that it keeps anything (even light) from escaping? A black hole is an area of such immense gravity that nothing -- not even light -- can escape from it.

What is a black hole?

 

Watch this video to find out more about these areas of immense gravity!

Gravity on Earth

Gravity is very important to us. We could not live on Earth without it. The sun's gravity keeps Earth in orbit around it, keeping us at a comfortable distance to enjoy the sun's light and warmth. It holds down our atmosphere and the air we need to breathe. Gravity is what holds our world together.

11. What is the role of the sun’s gravity? To hold our earth together 

12.   Can humans live without gravity? We will not be abl to breath and we will no longer be able to live on erath

However, gravity isn’t the same everywhere on Earth. Gravity is slightly stronger over places with more mass underground than over places with less mass. NASA uses two spacecraft to measure these variations in Earth’s gravity. These spacecraft are part of the Gravity Recovery and Climate Experiment (GRACE) mission.

13. Describe where Gravity in Earth is slightly stronger. It has heaps of mass in the ground so there is a heap of gravity in the ground 

The GRACE mission helps scientists to create maps of gravity variations on Earth. Areas in blue have slightly weaker gravity and areas in red have slightly stronger gravity. Image credit: NASA/University of Texas Center for Space Research

GRACE detects tiny changes in gravity over time. These changes have revealed important details about our planet. For example, GRACE monitors changes in sea level and can detect changes in Earth’s crust brought on by earthquakes.

14. List 2 things that the GRACE mission can do for Earth.

i) changes in sea level 

ii) changes in Earth’s crust brought on by earthquakes.

 15.  Gravity on Mars

List 5 or more facts about GRAVITY ON MARS in the space below. You can copy and paste and add images. Save in your Hurumanu 3 File.

1 It is weaker than earth's gravity due to the planet's smaller mass. The average gravitational acceleration on Mars is 3.72076 ms−2 (about 38% of that of Earth) and it varies laterally.

2 On Mars the Sun appears about half the size as it does on Earth.

2 Mars is sometimes called the Red Planet. It's red because of rusty iron in the ground. Like Earth, Mars has seasons, polar ice caps, volcanoes, canyons, and weather. It has a very thin atmosphere made of carbon dioxide, nitrogen, and argon.