Have you ever wondered what Earth’s orbit looks like outer space? (Pause)
All the time? Me too
Take a look at these diagrams. Which one most closely resembles the shape of Earth’s orbit? (pause)
Picked C? or D? Don’t be dumb!!
If you picked C or D at least you’re not in the minority.
Most people selected one of those options. Why? Probably because that is how you are used to seeing them in textbooks. (Show picture examples) like this? Or like this?
So why would they show it like this? Just to confuse us? Sounds like at teacher (hold for laughter ;)
Well first, they did it because it is impossible to show scale of the universe in such a small image.
The distance from the earth to the sun is 92.960.000. How could that be shown on a diagram? C’mon, don’t be dumb!!
The earth is 94,500,000 km from the sun here (show) and 91,400,000 here (show). In terms of the solar system, that is not that big of a difference. When you zoom out, its like trying to tell the difference between an ant and a truck from outer space! Not possible!!
Diagrams often overaccenturate the distances to help you remember that there ARE differences.
Lastly, this diagram is actually very close to representing the true eccentricity of the orb it.
No, no eccentric like my cool outfit, eccentricity of an orbit.
Eccentricity is a number between 0&1. Which shows the shape of an objects orbit as it moves around the sun.
A number that is closer to 0 is more circular, with 0 being a perfect circle. A number that is closer to one is flatter or more oval, with 1 being a flat line.
Earth’s eccentricity is 0.017, that’s pretty darn close to 0, so pretty close to a perfect circle. Our orbit after all is close to a perfect circle.
As you can see at the scale of the drawing, the orbit of the sun is indistinguishable from a perfect circle, making A the only answer!!
But don’t feel bad if you picked the wrong answer! It’s not your fault, it’s the textbook. So next time you see a diagram like this (show) or this (show), you tell them, Don’t be dumb!!!!!!!