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Meteorites Brought Ingredients of Life To Earth
Meshach writes "A new analysis of a meteorite found in Antarctica is leading scientists to think that life on Earth may have come from outer space. Chemical analysis of the meteorite shows it to be rich in ammonia and containing the element nitrogen. Nitrogen is found in the proteins and DNA that form the basis of life as we know it. The prevailing theory is that our planet may have been seeded by a comet or asteroid because the formative Earth might not have been able to provide the full inventory of simple molecules needed for the processes which led to primitive life."
..the meteorites were intelligently designed!
Boom.
THL phish sticks
There are those who believe that life here began out there, far across the universe... Some believe that there may yet be brothers of man who even now fight to survive somewhere beyond the heavens.
Not quite, complex organic compounds are found throughout our solar system. For example, on Titan it literally rains organic compounds that, when mixed with water, form amino acids. It is a plausible hypothesis that a third party could have brought such compounds to earth but it is also equally likely that earth simply formed them on its own. If Earth could have formed them on its own it doesn't require the third party hypothesis.
Carl Sagan quotes get you an automatic +5 on all posts.
Seriously, I find ideas like this to be unsatisfying because they just pass the buck. Why is it any more likely that life would arise in a comet, asteroid, or other planet than it would be for life to arise on earth? Maybe if the earth was wiped clean by some cataclysm, but I don't know of anyone who's proposed that.
To be fair to modern observational evidence versus historical record, historical record often isn't really all that good. Even big, fairly educated civilizations like the Romans didn't leave behind particularly reliable history. Take Caligula, for example, we know a few things about him, but many of the things we think we know are probably just made up. Historians throughout the ages have also often been popular fictional writers and little effort seems to have been put into distinguishing between their fictional works and their factual ones at the time (of course, they were writing for a contemporary audience who probably knew through context). Not to mention all of the propaganda.
On the observational evidence end, dating by geologic layers isn't perfect, but it's still pretty good at telling us that A happened before B, which happened before C. Sure, the dates we ascribe to the events aren't perfect, but, unlike recorded history, we usually have a pretty good idea of what actually happened. We can see flood, fire, meteorite impact, earthquake, continental drift, this species vanishing, this one arising, 1000s of different species all over the globe vanishing at once, etc., etc. Even geological evidence isn't perfect and it apparently can even lie sometimes, but nowhere near as much as a human writer who may well be on drugs, just plain insane, repeating common misconceptions and rumors as fact, or just plain lying like crazy to support an agenda.
So the Earth's atmosphere contains about 4*10^19 kg of Nitrogen (surface of the earth * 100 kPa/g * 80%). That's a *lot* of mass. A 10 km asteroid (like the one that could have wiped the dinosaurs) is maybe 10^12 kg. So it would take more than 10 *millions* of those to provide the Earth with its current atmosphere -- assuming these asteroids were pure frozen nitrogen.
Another thing I don't quite understand is why the nitrogen would have to come from somewhere else. As far as I know, stars produce plenty of it (CNO cycle and all), so if we have carbon and Oxygen, why not nitrogen as well. Am I missing anything?
Opus: the Swiss army knife of audio codec
If you're going to cite Occam's Razor, you need to understand what it actually says. It's not just "the simplest solution is usually the correct one". There is one particular way that Occam's Razor can identify which arguments are objectively simpler than others. There is a very narrow range of arguments that can be compared with Occam's Razor. What it actually states is that if you have two comprehensive explanations for something that have the following form:
Explanation 1:
Explanation 2:
Since both explanations fully explain the same subject, Occam's Razor states that explanation 2 is less likely to be true as it is objectively more complex, since it is a superset of explanation 1, sharing parameters a,b and c, with parameter d simply introducing more opportunities for the explanation to be incorrect.
What you are trying to compare with Occam's Razor are apples and oranges.
Explanation 1:
Explanation 2:
Neither of these arguements is a superset of the other, so they can't be compared using Occam's Razor.
Although there are more parameters to the first explanation, there is no way to objectively measure or even define the "complexity" of each individual parameter to check that even if you add them all together, if they are more "complex" than explanation 2
(1.21 gigawatts) / (88 miles per hour) = 30 757 874 newtons