Does the spin of the earth affect flights?
Does a flight take longer if the plane is flying against the spin of the earth?
Dominic - Well in fact, what's important is the plane's speed relative to the Earth's atmosphere - the air around it because that's what's giving it its lift up into the air and that's what is providing the the friction which is meaning it's having to thrust to keep going forward. The Earth's atmosphere is rotating with the surface of the Earth below it. The reason is, because it's got friction with the land masses beneath it and that means the air is always being pulled to rotate with the Earth. So in fact, because the air above us is rotating at the same speed as the land below, and what matters is your air speed - your speed versus the air - it doesn't matter whether you're going with or against the rotation of the Earth.
Dave - The one thing I would say with that is that there are some latitudes where the wind tends to blow in one direction. So, in our latitude, the prevailing winds from the west and they get even faster as you are higher up. So, it's a lot quicker to fly from the states to here than from us, back to the states. So, it's actually quicker to go against the direction of the spin of the Earth than with it, it just happens to be the way the air is moving. Other places, the wind is in opposite directions and they'll have the opposite effect.
Dominic - And I guess the other thing to say is that if you're going above the Earth's atmosphere into space then satellites all do go from east to west because there, you're above the Earth's atmosphere. You haven't got this drag from the air anymore and it is a lot easier to get into an orbit that goes with the Earth's rotation rather than against it.
Chris - A little bit of drag though isn't there because the International Space Station and some of the lower flying satellites have to be boosted every so often because they are experiencing a little tiny bit of drag from wisps of atmosphere out there.
Dominic - That's right. The International Space Station is in quite a low orbit, at about 130 or so kilometres up and it does have to thrust about once a month to maintain altitude.