If the Earth suddenly started spinning in the opposite direction, everything not fixed to the ground would be launched at 3200 km/hr eastward. This would happen because everything will still be rotating due to inertia towards the east, while the ground suddenly moves towards the west. Now the sun rises from the west.

If the Earth was rotating from North to South, the north pole and south pole would both be on the new equator, and the new north pole and south pole would be *somewhere* on our current equator. Near the equator the seasons actually come twice a year.

When you jump, there is no outside force acting to slow you down, so you stay in the same position, relative to the plane. If you were on the outside of the plane however and you jumped up, you would have something pushing against you (all the air that is smashing into you at 500 mph) and would be pushed backwards.

Now the mass of the Earth is 5.97 x1024 kilograms. So, force equals mass times acceleration, to get the thrust required to accelerate the Earth at the required rate, we just multiply the above two figures together and obtain a thrust of 2.27 x 1011 N, or 227 billion newtons.

Although it’s theoretically possible to change the orbit of a planet, it’s probably completely impractical. Moving Mars, for example, to an orbit closer to the Sun would require decreasing its kinetic energy enormously – perhaps by shunting large asteroids into close encounters with it.

to do everything you can to achieve something: He’ll move heaven and earth to get it done on time.

NASA is still aiming for human missions to Mars in the 2030s, though Earth independence could take decades longer. He laid out 2030 as the date of a crewed surface landing, and noted that planned 2020 Mars rover would support the human mission.