A few weeks ago, I went to see the movie The Good Dinosaur with some friends. It was a great movie and I definitely think that if you are reading this you should go see it. Since this is a blog about physics, let's talk about that!
As the movie begins, a asteroid gets dislodged from the asteroid belt between Mars and Jupiter. This asteroid starts moving directly towards Earth. As it gets closer to Earth, it enters the Earth's Gravitational Field. It bursts into flames as it enters Earth's atmosphere as there is a sudden change from the vacuum of space where there is no friction to the friction filled air. This sudden change causes a change in energy. Energy is lost in the form of heat. The heat is strong enough to cause flames. So it starts off a pretty accurate representation of physics. Then, by some chance, the asteroid misses Earth. This is impossible since there was no force that acted upon it to change it's direction. The asteroid was already feeling the affects of Earth's gravitational pull. The asteroid should have hit Earth, but that would mean the movie would have been over in the first few minutes. So we will have to pardon Pixar's incorrect physics since they did do a good job of telling a story.