Hi Guys

Johannes wrote...

I’m still searching:
for anyone (or any place) that has information on how much radioactive material is in the atmosphere these days.

[enough to skew the radioactive carbon in living things since 1945]

Also I’m interested in knowing if anyone has made the connection that radioactivity in the atmosphere may be ‘heating’ (imparting kinetic energy to) the atmospheric molecules.

[not a lot. the upper atmosphere is energised a lot more via cosmic rays and the Sun, than man-made radioactives]

Then furthering that thought, I’m interested in knowing how fast the atmospheric molecules are moving in the ‘thermosphere’ and above it.

[the exosphere and thermosphere are pretty thinly spread-out and a lot of the particles within are on ballistic trajectories. Hence the term "perfect gas" loses meaning since the particles rarely collide.]

I know that any object that has the velocity of seven miles per second can escape the Earth’s gravitational influence.

[for normal gas conditions a small percentage of the gas in question will have an energy higher than escape velocity, because the distribution curve of energies is spread wide at higher temperatures. Monatomic oxygen at 1500 K is doing 1200 m/s on average so only a very tiny fraction is doing escape velocity, but in the case of hydrogen atoms the average velocity is ~ 5000 m/s, and so a high proportion are going faster than 11,000 m/s.]

I also know that radioactive decay of atomic nuclei imparts kinetic energy to the surrounding atomic elements; besides causing the surrounding elements to become radioactive.

[some surrounding elements might become radioactive. Some. Depends on the material]

It has been proposed on this board that the Earth’s magnetic field will somehow prevent energetic particles from escaping the gravitational field of the planet.

[no. they are trapped in the magnetic field. Gravity is irrelevant to particles with MeV energies like in the van Allen Belts.]

The implication seems to be that radiation, man made or natural, including the VanAllen belt has no accelerating influence on the activity of air molecules.

[It does. The flow of high energy particles from the solar wind boosts various atoms to beyond escape velocity creating the "polar wind" - see this old NASA link...

http://science.nasa.gov/newhome/headlines/ast08dec98_1.htm ]

I’d like to know the basis of the conjecture that magnetic fields can prevent energetic particles from moving faster than seven miles per second.

[They don't. They just force the particles to move in spiral paths within the magnetic field.]

As I understand it, the Sun has a greater escape velocity than Earth and there are magnetic fields associated with the Sun, yet it is able to expel massive quantities of energetic particles into space . Why could this not happen on Earth?

[It does]

So far I have found many interesting and informative web sites; non of which give the information that I need.

[keep looking]

Adam :o)