2. Gravity
Gravity is something that you can’t see but we need. If we didn’t have this, we would be floating in the universe.

3. Facts
If we didn’t have gravity, none of the stars and planets would keep their round shape.
Gravity allows the sun and the Earth to keep their atmospheres.

4. More about gravity
The Moon and the Earth are connected by gravity because the Moon has less mass and the Earth has more mass so it goes around it. That is why they say that the apple fell on Newton, because the Earth is bigger than the apple so it fell, so Newton didn’t fall on the apple.

5. Gravitational waves Last year scientists observed
gravitational waves produced
by two black holes long ago.
The two black holes had similar mass, they collapsed
and the impact made those gravitational waves.

6. Black holes
A black hole is an astronomical object that has a mass so large that it attracts everything that passes near it, even light, so it is seen as a black spot on the sky.
Scientists believe that there is a black hole at the center of our galaxy, the Milky Way.
Now, Steven Hawkings showed that a black hole isn’t all black: it actually emits light.

7. INTERESTING PHYSICS VIDEOS to WATCH
THE MECHANICAL UNIVERSE: Recommended Videos for Y12 Physics
Index of all episodes: 
1. Introduction  This preview introduces revolutionary ideas and heroes from Copernicus to Newton, and links the physics of the heavens and the earth.
2. The Law of Falling Bodies  Galileo's imaginative experiments proved that all bodies fall with the same constant acceleration.

8. Thank you for watching😁
BY MARCOS