Is Earth's Atmosphere an Import?

garg0yle writes "One of the questions about the formation of our planet is: where did the atmosphere come from? One theory is that the oxygen, nitrogen, and other gases were part of the coalescing ball, and 'seeped out' during the final stages of the planet's formation. However, a new article at Wired says isotopic analysis of krypton and xenon indicates that they (and the rest of our atmosphere) may be of extraterrestrial origin, either arriving via comets or being swept up from gas clouds."

Comments

Rubbish...

[Anonymous Coward]

I'm an atmosphere skeptic.

The existence of the atmosphere is a liberal hoax perpetrated on us by the scientific community.

Can you see it? No. What are they trying to hide?

Re:Rubbish...

[Tanman]

First, the Earth is a SPHERE. Now they talk about atmoSPHERE. Coincidence?

Now, I'm not saying the same yahoos who say the Earth is round also say some magic dust from outer space fills my lungs with every breath, but don't you think it's interesting that I'm the only one at least asking questions about their true intentions?

Re:Rubbish...

[Arthur Grumbine]

Did the atmosphere rape and murder a girl in 1990? There are witnesses to the fact that the atmosphere was at the location of multiple rapes and murders in 1990. While the rapes and murders were happening!! At the very least the atmosphere should be charged as an accomplice, as crime scene investigators have conclusively demonstrated that the alleged rapists and murderers in the majority of the cases would have been unable to perform the heinous deed if the atmosphere.had not been present.

Who is going to take responsibility for answering our questions? The atmosphere has remained eerily quiet in the face of such bold questions! We must demand answers!

Re:Rubbish...

[martas]

For a long time now, I have been afraid to come out with my story, but since this issue has been raised, I just can't stay quiet any longer. It is my duty as a citizen to report that for as long as I can remember, the atmosphere has been orally violating me. What's worse, my parents have known about this all along, and they have stood by and let it go on. In fact, as soon as I was born, they let the atmosphere touch me in the most inappropriate places. I also know of many other individuals who have been subjected to similar treatment by the atmosphere, though I won't name any of them - I will leave it up to them whether or not they decide to follow my example and tell the world about this horrible ongoing abuse.

I hope the authorities will act upon my testimony, and finally put an end to the atmosphere's series of crimes.

Re:Who cares?

[Kerrigann]

Maybe it would give us hints about what to look for in other solar systems when looking for rocky planets with similar atmospheres?

Maybe it would tell us something about whether or not our type of atmosphere is rare in the universe?

Who knows, it might be useful. It should be at least as useful as studying the mating habits of the short-tailed horned lizard, or a million other things scientists study.

Re:comets

[noidentity]

You forgot to capitalize an instance of "water" in your first and last sentences. I also think you should capitalize "moons", "worldly", and "substances", for good measure.

Wha...?

[Anonymous Coward]

It's hard to understand how you can extrapolate a whole atmosphere's origins by looking at a couple of very rare gases like krypton and xenon.

Given that all the elements that make up the Earth were manufactured in the same solar furnace(s) why is it necessary that some originated separately from others? How do you then explain the huge atmospheres of the Gas Giants? It would take an unlikely number of very large asteroids to do the job.

This hypothesis suffers from the same shortcomings as the Transpermia idea. It just moves the problem elsewhere, at best.

Re:Wha...?

[wizardforce]

Incorrect. Isotopic ratios vary depending on the conditions in the planetary nebula that formed our solar system. The disk tends to fractionate into "layers" with refractory materials tending to be toward the sun and volatiles tending to be fairly far away from the sun. Volatiles like Hydrogen and Helium would be expected to accumulate around large terrestrial masses ~50 Earth masses out around Jupiter and beyond. Volatiles like Hydrogen and Helium don't accumulate as significantly near terrestrial planets as close as the Earth is due to the fact that the Earth and similar terrestrials were of insufficient mass to retain significant Hydrogen and Helium. This is due in large part to the density of the nebula which formed our solar system.

Re:Wha...?

[Antique Geekmeister]

Oh, dear me. I can *see* the little propellers tied to your wrists helping you wave your hands.

In this case, the isotopic ratios are small fractions of the differences between the masses of different actual elements. The profound mass differences and related escape velocities of different gaseous _elements_ far overwhelms the differences in masses between the distinct isotopes: thus, any atomic weight related differences are nearly irrelevant. The possible exceptions are tritium and deuterium, which are respectively 3 and 2 times the mass of hydrogen atoms, but they're unstable enough that they're unlikely to come from ancient sources. Rather, they arise as byproducts of certain types of fission, especially tritium. In their cases, plain hydrogen ions or molecules can be lost to interplanetary or interstellar space relatively easily. Deuterium lasts, tritium has a half-life of 12.5 years, so it's long-gone.

But do _not_ confuse the "density of the nebula" with the mass or the atmosphere of Earth and other planets. I can see where that would be dominated by the overall mass of the nebula from which they formed, but the proximity of the planets to the Sun influences the elimination of atmospheric hydrogen and light chemicals by keeping the planets warmer and allowing them to lose their lighter chemicals to space.

Some Krypton isotopes are stable and thus more likely to reflect ancient conditions than tritium, for example. And refinement via normal, chemical means available on a planetary mass or its crust are unlikely to refine the isotopes, so it's reasonable to make some guesses about the original materials of the atmosphere's creation from the isotopic ratios.

Science?

[jwiegley]

How the HELL did this article get filed under "science".

Venus has a significant atmosphere. Saturn has an atmosphere. Neptune... atmosphere. Jupiter... ALL atmosphere. Hey, look at that! All the planets larger than Mars have a significantly thick atmosphere.

Maybe it's as simple as their gravity is sufficient to trap gasses.

Please refile this article under "Intellectually Bankrupt" instead.

Re:Science?

[MightyMartian]

None of the planets you list have the proportionally large amounts of O2 that Earth does. It's not that Earth has a large atmosphere, it's that the atmosphere is in so many ways different from even the other Earth-like bodies (hint Venus and Mars' atmospheres are dominated by CO2). The gas giants are a totally different creature; they are largely made up of hydrogen.

Re:Who cares?

[Narpak]

Honestly who cares?

Atmospheric scientists?

Re:Who cares?

[TimSSG]

FYI:

The is only a single Solar System in this universe.
That is the name out our star system. Please use star system instead of Solar System when not referring to our star system.

Tim S.

Re:Who cares?

[TapeCutter]

The entire Earth came from dust and gas. Sure some of it may have arrived a little late in big chunks or clouds but the reason our atmosphere has the composition it does now is that life changed it from something like Titan's atmosphere to what we see today. In otherwords life and the atmosphere co-evolved on this planet and they continue to do so, neither would exist in their current form without the other.

The atmosphere, lithosphere, and hydrosphere are collectively know as the biosphere. If we find a spectra from another planet's atmosphere that has a similar composition to ours then our current state of knowledge would demand the conclusion that life created it. And yeah, it's worthwhile looking. IIRC scientists have already determined the atmospheric composition of several exoplanets.

Re:Who cares?

[Kerrigann]

Wow, 'expoplanet'. Dunno how I typed that.

It's like the sales-convention planet.

It will be the first to be nuked out of existence from orbit.

Re:Weird conclusion

[FatdogHaiku]

Gravity is a lie perpetrated to keep the people down!

Re:Who cares?

[martas]

the full implications of knowledge cannot be predicted.