Comets Probably Seeded Earth's Nitrogen Atmosphere

KentuckyFC writes "One of the biggest puzzles of astrobiology is the origin of the Earth's oceans and atmosphere. One favored theory is that our water is the leftovers from a bombardment of comets early in Earth's history. But the ratio of hydrogen and deuterium in the oceans doesn't match the ratio in the four comets measured so far (Halley's, Hyakutake, Hale-Bopp and C/2002 T7 LINEAR). Now a new analysis of the ratio of nitrogen-14 and 15 isotopes in these comets and on Earth places new limits on how much of our environment could have come from comets. On the one hand, the astronomers who did the work say that no more than a few percent of Earth's water could have come from comets. But on the other, they say that the ratio of nitrogen isotopes in these comets almost exactly matches the ratio in Earth's atmosphere. That suggests that while Earth's oceans must have come from somewhere else, Earth's early atmosphere was probably seeded by comets."

It is possible, but not certain

[comet63]

The article notes that the ratio of the nitrogen isotopes matches what is in the earths atmosphere. It seems to me, that just makes it possible that the comets are a significant source of the nitrogen on Earth. It is also possible that the nitrogen in the comets and in the atmosphere came from a common source.

Yes, it is a mystery

[justinlee37]

If those passages aren't a mystery to you then I say you need to go back to elementary school and learn how to read critically. Who is this God character? How did he create the heaven and the earth from something without form, out of a void? There are obviously some details missing and I demand a refund for this explanation of the universe you have sold to humanity.

Re:Determining the origins of ....

[alexhard]

>method of guessing based on simply "interesting patterns"

That would be the SCIENTIFIC method (or at least the first part of it), the source of all scientific advancement since whenever.

Re:That seems to make some sense.

[TheTurtlesMoves]

By your reasoning only economist should comment on topics of economy, climatologists on topics of global warming, etc...

This is /. you are allowed to speculate and the reader shouldn't be such an idiot to assume every post is by an expert or a lawyer (IANAL crap).

Even more important experts can and should be questioned. People outside the field can give suggestions and should criticize experts if they cannot justify their point of view. The only times we get a group of people that think they cannot be questioned by outsiders... they are usually wrong.

And what are your credentials? Modding expert? Modding consultant?

By the way I am an astronomer by training... Grandparent has a good point.

Re:sure is taking a lot of faith

[amicusNYCL]

That's the good thing about science: when the authors not only describe their conclusions, but also show all of the evidence they used to come to their conclusions, you can examine the evidence yourself and determine if you come to the same conclusion. You don't need to have faith in the authors when they give their reasons for their conclusions.

Re:Determining the origins of ....

[ceoyoyo]

How do you prove a story wrong? Particularly a vague, self contradictory story? Many of the things we know about the world appear to contradict what's in the bible. Bible advocates either twist bible stories so the apparent contradiction goes away, or they simply ignore the science.

I notice you didn't even try to reply to the content of my post, but rather cooked up some extremely questionable claim that you stated as fact, instead. Typical.