Our atmosphere?

Question

Why don't we eventually lose our atmosphere to space?

As we get closer to space the gravitational forces keeping the atmosphere from going into space must be negatively balanced by the diffusion of air into space (which has no atmosphere).

Although the process may be slow, over eons shouldn't we have by now totally lost our atmosphere?

Answer 1

There are two main things that keep our atmosphere together. One, of course is gravity. Although the gravity is weaker at the outermost part of earth’s atmosphere, the gravity is still quite strong. Many people think that astronauts have escaped the earth’s gravity once they are in space, but they haven’t. Astronauts float around in space because they are orbiting the earth. This orbit keeps them from getting pulled in toward the earth (like centripetal force).

The other thing that’s preventing the atmosphere from escaping earth is the earth’s magnetic field. This magnetic field repels most of our suns solar wind, which would otherwise blow away our atmosphere over time.

Answer 2

We do lose atmosphere to space. But it is slow, since Earth's gravity and chemical processes in the atmosphere tend to keep it bound to Earth.

And the Earth is constantly replenishing the atmosphere from volcanic outgassing of water and other gases.
Plus meteors are constantly bringing small amounts of gases and other materials to Earth.

Its estimated that the Earth has a net loss at most 1% of its atmosphere since it formed 4.5 billion years ago.

Answer 3

In the uppermost layer of our atmosphere the molecules are excited by cosmic rays and theyfly off at high speed in all directions, some of them fly off into space and are lost, but the over all loss is negligible.

Answer 4

NO.

You have forgotten that Gravity keeps our atmosphere here on the Earth. As it tries to escape for one reason or another, it is always pulled back to Earth by GRAVITY.

Answer 5

On Earth, muscles and bones develop in response to the environmental stress we put on them as we go about our daily lives. The major contributor to our environment on Earth is gravity. The force of gravity pulling us towards the surface of the Earth places strain on every part of our bodies both inside and outside. In order to remain upright and to protect our vital organs, land animals, like human beings need a strong skeleton.

Being in space takes a great load off our body's systems. In the microgravity of space, and in bodies of water where we do not feel the bulk of the force of gravity, skeletal bones do not have to support the weight of the body. As a result, living organisms like fish have evolved in a way different to land animals.

Fish still have bones to protect vital organs and to act as support for appendages, but the massive bone structures that are typical in land animals are not present. In space, humans no longer need heavy, weight-bearing bones (like the hip bone or tibia) since the force of gravity is no longer a concern.

The human brain is quite extraordinary. Within the first day or two in space, the brain adapts to a microgravity environment. Part of this adaptation results in the body beginning the process of shedding its skeleton. Every time an astronaut urinates in space, calcium, a crucial bone-building element, is lost. In fact they can lose up to 2% of their bone mass each month thus reducing the size and strength of their bones.

People suffering from muscular dystrophy and osteoporosis experience a similar loss of bone mass. In microgravity, the process of bone loss happens up to 10 times faster than on Earth.

Although the loss of bone mass is not worrisome for astronauts during space missions, when they don't have to rely on a strong skeleton to support their mass, it becomes a major concern when they return to the gravity environment of the surface of Earth. The molecular mechanism for this loss is not known. Space research into this phenomenon, with its unique microgravity environment, may one day result in treatments or even cures for the crippling diseases that affect almost 1.5 million Canadians.

Answer 6

earths poweful magnetic field prevents loss of atmosphere to space

Answer 7

probably unless we do something to stop it!