everything is still here

[lucky45]

I was just thinking,which I try not to do, But it occured to me that everything since the dawn of our planet is still here, What I mean is that all living things and non living things never left our planet into space. This means that all mater is still here but in a differant. Kinda like a recycleing proccess..

[ajb]

We gain matter from space. Do we lose any due to impacts? (for example)

[tomgwyther]

"everything is still here"

As far as I'm aware, the statement is pretty much correct. We gain a little bit from debris falling to Earth from space, We loose a little bit when we put probes and the like on other planets. Other than that, most of what is here on Earth now, was here billions of years ago, albeit in different forms.

[ydoaPs]

We gain matter from space. Do we lose any due to impacts? (for example)

 

Impacts and launches.

[Mr Skeptic]

Earth accumulates material from space debris (mostly dust), but occasionally a particularly large impact can knock some material into space. And of course, we have sent a few things into space ourselves recently. Mostly Earth gains mass though.

[CaptainPanic]

Don't forget about our atmosphere.

 

Significant losses and gains of "stuff" are probably in the upper atmosphere.

[ajb]

Don't forget about our atmosphere.

 

Significant losses and gains of "stuff" are probably in the upper atmosphere.

 

That also crossed my mind, does any significant amount of our upper atmosphere get "boiled off "? Presumably, this "topped up" by gases held within the Earth that are released during volcanic eruptions?

 

Someone must have done some calculations for this?

[the tree]

Presumably we'd be gaining that atmosphere back somehow, if it were only being topped up by volcanic activity then the net mass of the Earth would be slowly going down, which I'm sure we'd have heard about.

[insane_alien]

we are losing atmosphere to space. its dragged off by solar wind and just plain diffusion. butthe amount is pretty tiny. its only really hydrogen and helium that get far enough away for that to happen. more than enough gases stored in the earth to keep the atmosphere around.

[D H]

Earth atmospheric mass losses are about three kg of hydrogen and fifty grams of helium per second, which compared to the mass of the Earth is fairly tiny. However, 3 kg/sec is about 100 million kg/yr, or about 4×10¹⁷ kilograms over the 4.5 billion years the Earth has been around. The latter number of course assumes a constant rate over that 4.5 billion years.

[lucky45]

Thanks for the reply, I think it was an interesting subject. Ok, My question is:

Is is possible for anything to escapt the earth into the vacuum of space without some type of force behind it? Also wont all things even the lightest

of gassess be pulled back into our atmosphere buy our own gravity.

[Mr Skeptic]

Well, once the molecules get far enough away, they are nearly in a vacuum. The solar wind has fast moving protons, which if they hit a hydrogen atom are enough to knock it away, so long as it doesn't hit something else. This is a problem for smaller planets, like Mars.

[Sisyphus]

So in other words, yes, there is a force behind it: the bombardment by solar wind.

[Galindo]

So in other words, yes, there is a force behind it: the bombardment by solar wind.

 

Is it true that this is being cause by Earth's weakening magnetic field?

[Sisyphus]

Is it true that this is being cause by Earth's weakening magnetic field?

 

No. I happens no matter what. It is true that the Earth's magnetic field shields the Earth from the full effect of solar wind (without it we would have barely any atmosphere at all), but it isn't weakening.