If you know anything about space and physics, then you know just how perfectly shaped and positioned the Earth is to allow life. Many properties of where our planet lies in the solar system couldn't be changed and life continue to prosper, but what if they did? I mean, theoretically the earth could be twice as big, but humanity and nature would experience some pretty drastic changes. Check out the video below where Life Noggin will take you through the 'goldilocks zone' and where we call home.
Doubling the Earth in size sounds like the plot of a cartoon supervillain, but it provides and interesting avenue to flesh out some physics principles. Assuming, as does Life Noggin, that the Earth doubled in size but kept the same density, it would increase in mass by 8 times. Using the equation:
g= G * M/r2
Where g is gravity, G is the gravitational constant, M is the mass of the Earth, and r is the radius of the earth. When you plug in the values associated with a doubled-in-size Earth, you work out gravity to be about twice as much. This would be like carrying around yourself all day, which sounds really fun, right? Trees wouldn't grow as tall, friction would be greater, a lot of things we call constants now would be drastically different, and we would find it harder to live.
Let's just all agree that the Earth is good as it is, no supervillain needs to go doubling it in size.
[Image Source: Life Noggin]