The Spinning Atmosphere
A Visit to the Edge of Space
Helium Balloon
To get there I'm going to need the help of a team of people who know how to get to the edge of our atmosphere.
Our vehicle is a helium balloon. The balloon's journey will show us why the Earth's spin has such a strong influence on the atmosphere. We've attaches a GPS transmitter to track it's journey and four cameras will record everything the balloon sees.
To begin with, the balloon goes pretty much straight up. This is what you'd expect because the atmosphere spins with the planet. But then, the balloon starts to move sideways.
The balloon is being carried away from us. This reveals a crucial fact about the atmosphere. Although it spins with the Earth, the atmosphere isn't completely locked to the surface. It's actually a fluid, so it can move in different directions, at different speeds. Today, the balloon is being pushed east. We're driving at 50mph, yet it's still racing ahead of us, as it continues to climb. The balloon is now at 20,000 metres, twice the height at which airliners fly. It's nearly midday but the sky is black.
We think the balloon is near the top of it's trajectory, and up where it is, there's very little, very, very low air pressure, so about 95% of the atmosphere is below the balloon. Because the pressure's so low, the balloon will have expanded to about three times it's initial diameter, but that is about as much as it can take.
Balloon's Eye View
As it falls back through the atmosphere, the burst balloon reaches speeds of over 100mph.
The atmosphere is a thin layer of air that spins with the Earth. But it's also full of moving currents that help create the weather. It's tempting to think of these currents as random and chaotic, but they're not. They're organised into distinct patterns. And the way these patterns are organised is controlled by the spin of the Earth.
To see how spin can play such a powerful role, I've travelled tp Ecuador in South America for a very special drive.
