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We All May Have a Little Martian In Us
coondoggie writes "Men are supposed to be from Mars as John Gray's iconic relationship book would have you think, but new research presented this week suggests that in reality; we all may hail from the Red Planet. 'The evidence seems to be building that we are actually all Martians; that life started on Mars and came to Earth on a rock. It's lucky that we ended up here nevertheless, as certainly Earth has been the better of the two planets for sustaining life. If our hypothetical Martian ancestors had remained on Mars, there might not have been a story to tell,' Professor Steven Benner of The Westheimer Institute for Science and Technology said."
7). "Reverse seeding of life, from Earth to Mars, did not happen." This may be easier to support. Earth's gravity well is greater than Mars. However ruling it out will be extremely difficult.
Actually, some astronomers looked at this back in the 1970s, and concluded that at the bacterial level, Earth to Mars travel is fairly easy, and has almost certainly been going on since early in the Solar System's history.
The mistake people are making is thinking that impacts ejecting rocks are the way that bacterial would make such trips. The astronomers examined and verified the effectiveness of an entirely different mechanism. The Earth (and all the planets with atmospheres) has a "cometary tail" produced by the solar wind. This tail is mostly gases, of course, but it also includes a small proportion of dust-like particles. It turns out that this includes bacterial spores, which have been found at all levels of the Earth's atmosphere, and have probably been there for a few billion years.
The Earth's cometary dust tail is thin, but it is of interest to astronomers. Taking pictures through a haze of air and dust is more difficult than avoiding the air and dust, so some astronomers need to keep track of our planet's tail and avoid it when possible.
Anyway, measurements back in the 1970s did show that the Earth's dust tail contains small particles the size of bacterial spores, and since they exist in our upper atmosphere, they are to be expected in the tail. How long they can survive in space isn't well understood, but tests in orbit have shown some rather good survival rates of the spores when exposed to conditions near our planet.
So the solar wind has been pushing small quantities of Earth's air outward for a few billion years, and that includes assorted tiny dust particles and bacterial spores. This has to have "contaminated" all the outer planets with Earth's bacteria for all that time. Whether they've survived anywhere else isn't known, but Mars is the most likely place.
Some of the astronomers have also calculated the spread of our dust tail outside the Solar System. Most of it does escape eventually, and gets lost out in interstellar space. We make an orbit around the galaxy roughly every 220 million years, so since life arose on Earth, we've been spraying the galaxy with our bacterial spores for around 15 to 20 orbits.
How such spores survive out there, nobody knows, of course. But it's an interesting thing to consider when the "panspermia" hypothesis comes up. Any planet that develops bacterial life will, probably within a billion years or so, start spraying them out into the galaxy like we do, possibly contaminating any compatible planet anywhere else in the galaxy over the next few billion years.
(I recently read somewhere an estimate, based on current measurements of the solar system's dust, the likelihood of spores from Earth hitting Earth-size planets around stars at various distances. The numbers were nonzero, but I took them all with a grain of salt -- also included in the dust -- since so little is known about the reality of interstellar space and the likelihood of a spore surviving a trip that may last a few million years.)
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
And not that many years ago, the FBI insisted their scientists could tell you if the bullet that killed someone came out of the same box of bullets found in the suspects house, based on a spectral analysis of the lead in the bullet.
They had a whole bunch of scientists willing to swear to this in court under oath.
And it all turned out to be utter and complete bullshit. More than one defendant got out of prison on that one.
You can not know the origin of a random rock from outer space that lands someplace on earth. You can't even tell with certainty where a random rock from earth originated.
Sig Battery depleted. Reverting to safe mode.
Its because the organisms being talked about are likely some form of bacteria or similarly simple single celled organism. There are many, many varieties of that kind of life, and there seems to be at least one microorganism that can survive in almost every extreme condition short of raw flame, and I'm not even certain if that would stop them forever.
So, this is how I see it having gone down:
Life evolved on mars as single cellular organisms and those organisms spread all over the planet, including places where it was extremely warm, and places where it was chillingly cold. Some of those hardy organisms started to work their way deeper and deeper into some rocks in an exceptionally frigid part of the planet, where they lived, if not thrived, highly adapated to the cold, to the point where they could survive being frozen during the coldest parts of the martian year.
One day, during one of the several bombardments of the solar system by meteors and comets and whatnot, something struck the martian surface near these organisms hard enough to accelerate the rock they were living in out of mars' gravitational field. Coincidentially, this rock was also large enough that when it would eventually enter earths atmosphere, enough of it would survive that not every little organism in it would be fried from the re-entry heat.
So this rock floats in space and the little organisms in it get frozen. And I mean really frozen. Phillip J. Fry frozen. Because, you know, it's actually cold in space. And this rock drifts around, going who knows where for thousands, millions, maybe even billions of years, until it gets caught in earths gravity well. It falls down the well, hits the atmosphere and the outer layers start burning off, and the rest of it starts to warm up. The little organisms in the center of the rock get thawed out, and when the meteor hits one of the early earths primordial seas, some of these little organisms start to slip out of the micro-fractures that were inflicted on whatever remains of their rock.
Those little organisms find for themselves an environment that is alien, but useable. And they thrive. If not off the bat, then within a few generations thanks to how fast single celled organisms can evolve. At some point we get primordial earths first figurative algae bloom, and suddenly the seas are full of em! They start sucking up the methane and other gasses that were present in the early earths atmosphere, coughing out oxygen, and eventually the oxygen in the atmosphere exceeded the earths capacity to store it in rocks and we started to get an oxygenated atmosphere. The seas turned from green to blue as other gasses were driven out of the oceans and replaced by oxygen, and stuff started evolving until one day we arrive at a discussion where some people can wrap their heads around the plausible, yet highly speculative possibility that maybe life did in fact start on Mars instead of Earth, and other people simply can't handle such an awesome idea.
Exactly! Whenever I see claims that life started on Mars (or was brought here on meteors) I wonder why there is even a need for those hypotheses. You need pretty strong evidence that life COULDN'T have started on earth to resort to such a much less likely theory...