We may all be Space aliens

[stewie Griffin]

This is quite X -filish and very interesting.

Originally Posted by Yahoo7

Genetic material from outer space found in a meteorite in Australia may well have played a key role in the origin of life on earth, according to a study to be published on Sunday.
European and US scientists have proved for the first time two bits of genetic coding, called nucleobases, contained in the meteor fragment, are truly extraterrestrial.

Previous studies had suggested the space rocks, which hit earth about 40 years ago, might have been contaminated upon impact.
Both of the molecules identified, uracil and xanthine, "are present in our DNA and RNA," said lead author Zita Martins, a researcher at Imperial College London.
RNA, or ribonucleic acid, is another key part of the genetic coding that makes up our bodies.
These molecules would also have been essential to the still-mysterious alchemy that somehow gave rise, about four billion years ago, to life itself.
"We know that meteorites very similar to the Murchison meteorite, which is the one we analysed, were delivering the building blocks of life to earth 3.8 to 4.5 billion years ago," Martins told AFP in an interview.
Competing theories suggest nucleobases were synthesised closer to home, but Martins said the atmospheric conditions of early earth would have rendered that process difficult or impossible.
A team of European and US scientists showed the two types of molecules in the Australian meteorite contained a heavy form of carbon - carbon 13 - which could only have been formed in space.
"We believe early life may have adopted nucleobases from meteoric fragments for use in genetic coding, enabling them to pass on their successful features to subsequent generations," Martins said.
If so, this would have been the start of an evolutionary process leading over billions of years to all the flora and fauna - including human beings - in existence today.
The study, to be published in Earth Planetary Science Letters, also has implications for life on other planets.
"Because meteorites represent leftover materials from the formation of the solar system, the key components of life - including nucleobases - could be widespread in the cosmos," said co-author Mark Sephton, also at Imperial College London.
"As more and more of life's raw materials are discovered in objects from space, the possibility of life springing forth wherever the right chemistry is present becomes more likely," he said.
Uracil is an organic compound found in RNA, where it binds in a genetic base pair with another molecule, adenine.
Xanthine is not directly part of RNA or DNA, but participates in a series of chemical reactions inside the RNA of cells.
The two types of nucleobases and the ratio of light-to-heavy carbon molecules were identified through gas chromatography and mass spectrometry, technologies that were not available during earlier analyses of the now-famous meteorite.
Even so, said Martins, the process was extremely laborious and time-consuming, one reason it had not be carried out up to now by other scientists.

[Jan Willem]

Coincidentally (or not) I saw a fragment of a documentary about this subject on TV today, it was new to me that life very probably did not originate on Earth but was brought to this planet by meteorites. As some sort of bacteria, they said, who were able to survive the most extreme conditions in the universe, as is still the case nowadays with bacteria living in geisers (Iceland) or hot lava. There's no reason to think life is only possible and existing on our planet, although there's also no reason to assume these living creatures would in any way be similar to us (as is the case in most movies...6 feet high, two legs and two arms, a head with eyes, a mouth etc ). As opposed to most mammals which are utterly similar to us, although some people still refuse to realise this and claim humans aren't animals. Based on our superior mental abilities they say...I heard the recent natural disasters in South-Asia were magically predicted by the local elephants (that sounds funny ) who were all running away, while there was no sign yet

[Maca (Mod)]

The Earth finished forming around 4.5 billion years ago, and life sprouted more less 3.8 billion years ago, so the dates match (one of lessons os the classes I'm teaching deals exactly with this kind of stuff ). My only reservation about this was how the hell a molecule like RNA would "survive" after the extreme temperatures and conditions of a meteor crash, but there are bacteria living in ice and lava and stuff, so there's a possible answer.

And yeah, I live in the middle of the Pacific ring of fire, so we have earthquakes here all the time, and I have grown up hearing that animals can sense seismic disturbances and they start freaking out early, so they can tell you when a big earthquake is coming. But I have never seen it personally. That must be scary as hell.

[stewie Griffin]

Do you teach biology? Some bacteria and viruses are pretty resistant to extreme temperatures. Maybe its a case of thinking outside the box; that there is more to life than what science suggests. Ok getting a little Fox Mulder-ish now.

[Jan Willem]

Science doesn't suggest anything, scientists do. If there are reasons to believe or at least consider and investigate these new possibilities, then that's automatically science. Neither does science rule out religion, the supernatural etc..Some scientists do, freely extrapolating that what is known to a field science can never grab. I think they are too eager to adapt a static position, to belong to a certain dogmatic group. Which I think can extremely damage the neutral nature of science.

[Maca (Mod)]

Originally Posted by stewie Griffin

Do you teach biology? Some bacteria and viruses are pretty resistant to extreme temperatures. Maybe its a case of thinking outside the box; that there is more to life than what science suggests. Ok getting a little Fox Mulder-ish now.

Yeah, I'm a biologist, and in my Evolution class, which is the last one we take after we've gone through 4 years of all the other subjects, we talked about the origin of life. And if I remember well, it's not even that controversial to think that life on Earth came from outer space, it's been a theory since a long time ago.

I'm not sure if I'm remembering well or not, but I think that scientists who think life as we know it in our planet today originated here and didn't come from outer space use the carbon-based life structure as their main argument. They say that carbon is a very common and prevalent substance here on Earth and not in other places of our solar system, so if life had come from elsewhere, it should be sulfur-based or based in other elements.

But yeah, bacteria and viruses can be pretty resistant to extreme conditions, so I think that is a very valid point. It's such a big mystery, it would be great to find out the answer sometime.

[stewie Griffin]

I know theres been debate about whether or not life could have previously existed on Mars. They found channels or something which lead to the speculation that there could have been water on the planet years ago.

There are lots of galaxies and solar systems beside our own. Who knows, some form of life could have originated there.

[Jan Willem]

Originally Posted by Maca

I'm not sure if I'm remembering well or not, but I think that scientists who think life as we know it in our planet today originated here and didn't come from outer space use the carbon-based life structure as their main argument. They say that carbon is a very common and prevalent substance here on Earth and not in other places of our solar system, so if life had come from elsewhere, it should be sulfur-based or based in other elements.

They mentioned that in the TV documentary too, they said that the nebulae (if that's the right word) in the universe, which we would be able to see all the time if we hadn't massively turned the lights on on planet Earth, exist of carbon and not of what they always thought. (I think it was hydrogen)

[Maca (Mod)]

That's right there was that whole debate about the water in Mars. I don't remember if they found any signs of life there though. I remember that Mars definitely had liquid water, and now it exists as massive glaciers just beneath the surface. Mars lost its atmosphere at some point which caused all the water to freeze, it's a bit smaller than our planet and it's gravity couldn't keep the atmosphere around it.

[stewie Griffin]

Yeah, I read about that in this morning's paper. I doubt they would find any signs of life as it would most likely be microscopic; or extinct. I thought they had found some other planets with simlar qualities to Earth and not far from stars which could have provided heat and light. I really can't remember lol.