The Role of Gravity and Inertia in our Solar System

Remember how I told you our Sun is the largest object in our Solar System, and because of this greater mass, all the gravity in our Solar System is because of the Sun?  Well, gravity is constantly pulling on all 8 planets and dwarf planets every day...Why don't the planets get pulled into the Sun? 

Whoa!  That was a lot of information...basically, what this scientist is trying to tell us is, that, because the planets are moving (INERTIA) already and the Sun is massive (GRAVITY), together, gravity and inertia is what is keeping us from flying into the Sun.

The Sun is pulling us and the Earth is trying to move or escape.  Is there an escape velocity?  Look at this crazy table of escape velocities of different celestial objects:

Body	Mass	Escape Velocity in Kilometers/ Second	Escape Velocity in Miles/Hour
Ceres (largest asteroid in the asteroid belt)	1,170,000,000,000,000,000 kg	.64 km/sec	1430.78 mph
The Moon	73,600,000,000,000,000,000 kg	2.38 km/sec	5320.73 mph
Earth	5,980,000,000,000,000,000,000 kg	11.2 km/sec	25038.72 mph
Jupiter	715,000,000,000,000,000,000,000,000 kg	59.5 km/sec	133018.2 mph
Sun	1,990,000,000,000,000,000,000,000,000 kg	618. km/sec	1381600.8 mph
Sirius B (a white dwarf star)	2,000,000,000,000,000,000,000,000,000 kg	5,200. km/sec	11625120 mph

Hah!  The Earth would have to travel 25,038.72 miles per hour to escape the gravitational pull of the Sun.  Remember the two factors that determine the strength of gravity? 

Mass and distance.  Do you think Earth will be orbiting the Sun for another couple of billion years?

I think it's interesting to look at the masses of the objects...Look at the mass of the Sun and compare that to the mass of Sirius B a white dwarf star!!!  Holy Starmass!!

The Law of Gravity states something like this:  all objects in the universe have an attraction to each other...doesn't that kind of blow your mind?  We can't go anywhere in the universe and not be attracted to something.  So, how do scientists figure out how to get from planet Earth to planet Mars? 

It's all about mass and distance, the two factors that determine the strength of gravity....

Watch this next video and have your mind blown, or maybe better, some of the muddiness of gravity and inertia will clear up and you will see things more clearly?

Mind blown? 

Or mind cleared?