25 replies to this topic

[Liquidus]

Interesting read:

http://www.scienceda...70814093819.htm

Signs of life on comets that hit habitable planets and then begin the life cycle on that planet. In that case, how did the life forms get on the comets on the first place? The Prof in the article is suggesting that life didn't begin on earth, but rather in space, and randomly found it's way to earth. This might be old news for anyone following it previously, but it's news to me.

[Live Forever]

Yeah, I've seen some science shows on tv talking about that before. They even did some experiments showing how certain microbes and things could survive extreme speed, cold (of space), lack of air, etc. in order to make the journey of being blown off another planet somewhere and making the journey here. (they had this screen thing where they shot them at it at extremely, extremely high velocity then crashed them into it, and a small percent, but still a large amount overall--several thousand per square inch of earth--survived the encounter)

What we need is a larger data set. If we could find some life (no matter how small) on other planets or moons of other planets, or orbiting comets, then we could compare and see how similar it is on a micro level to us, and that would probably be enough to determine if life is "seeded" from place to place.

I've heard lots of scientists claim that it is the most likely explanation for life, but that still means it had to originate somewhere.

[Liquidus]

I've heard lots of scientists claim that it is the most likely explanation for life, but that still means it had to originate somewhere.

Well I consider it more plausible than the 'aliens are farming us here' theory . It makes a lot of sense if that was the case. It's amazing, what scientists know, is that we really know nothing. That might seem like a sad statement, but the truth is, it's the opposite, since we know so little, and are still alive, it goes to show that there's so much we've yet to discover, which is very, very exciting in my opinion.

[JohnDoe1234]

Yes, Panspermia, it's a pretty interesting idea.

Speaking of needing extra data sets, we might have some soon (of our own making that is)

This link is from a newsletter I get ever week from UniverseToday.com (pretty neat site if you ask me)
http://www.universet...est-panspermia/

[Live Forever]

This link is from a newsletter I get ever week from UniverseToday.com (pretty neat site if you ask me)
http://www.universet...est-panspermia/

Aaah, yes, that would test more completely if it is possible or not I suppose. I think all the individual items (extreme cold, high velocity, sudden stop, little air, etc) have been tested, and even multiple items all at once before to show that they are possible, but never in a "real life" scenario such as that. I think for "full" confirmation, we would still need to see some life from outside Earth, however.

[Lazarus Long]

Here is another article on the same effort.

http://www.space.com...ife_comets.html

Chandra Wickramasinghe, an astrobiologist at Cardiff University in the United Kingdom, and his team say their calculations show that it is one trillion trillion times more likely that life started inside a slushy comet than on Earth.

"The comets and the warm watery clay pools in comets are settings in which the organic molecules are transformed into living structures in comets," Wickramasinghe said. "That transformation is more likely in some comet somewhere in the galaxy than in any small pond on the Earth."

The new findings will be detailed in an upcoming issue of the International Journal of Astrobiology.

[Reno]

Since Earth is in space, technically life on Earth began in space.

[Live Forever]

Since Earth is in space, technically life on Earth began in space.

Good point. Everything (life or otherwise) begins and ends in space.

[Andrew Shevchuk]

I wonder what the fundamentalists have to say about this. Score: Science = 1, Religion = 0.

[Live Forever]

I wonder what the fundamentalists have to say about this. Score: Science = 1, Religion = 0.

Science has scored a whole lot more than 1 against religion over the years.

[mike250]

I've heard lots of scientists claim that it is the most likely explanation for life, but that still means it had to originate somewhere.

Well I consider it more plausible than the 'aliens are farming us here' theory . It makes a lot of sense if that was the case. It's amazing, what scientists know, is that we really know nothing. That might seem like a sad statement, but the truth is, it's the opposite, since we know so little, and are still alive, it goes to show that there's so much we've yet to discover, which is very, very exciting in my opinion.

thats true indeed and this is just the tip of the iceberg. as our knowledge improve who knows what other fascinating stuff we're going to discover.

[Luna]

Since Earth is in space, technically life on Earth began in space.

Good point. Everything (life or otherwise) begins and ends in space.

Can we skip the "ends" bit? [glasses]

[Andrew Shevchuk]

I wonder what the fundamentalists have to say about this. Score: Science = 1, Religion = 0.

Science has scored a whole lot more than 1 against religion over the years.

Yeah, but I'm counting on a case by case basis. The winner is obvious on the large scale. ;-)

[platypus]

Lichen has been shown to survive at least two weeks in space:

http://www.esa.int/e...FE_index_0.html

[Live Forever]

I wonder what the fundamentalists have to say about this. Score: Science = 1, Religion = 0.

Science has scored a whole lot more than 1 against religion over the years.

Yeah, but I'm counting on a case by case basis. The winner is obvious on the large scale. ;-)

Well just in the case of origin of life, science has scored a lot more. )

[AdamSummerfield]

It has been known for a while that comets can have up to around 120 different amino acids within them.

[AdamSummerfield]

In fact, some unlikely chemicals are found even in the vacuum of space, due to cosmic radiation. For example, there's hydrogen chloride, carbon monoxide, water and ethanol. Even particles found in space before on Earth such as the HCS+ ion, along with the surreal carbon ring, C3H2.

- Sezarus

[Luna]

Earth was found in space too!

[Lazarus Long]

Humor aside here is another interesting finding.

http://www.space.com...enine_dust.html
Life's Ingredients May Have 'Sprinkled' on Earth

By Dave Mosher, Staff Writer Space.com
posted: 11 September 2007
06:56 am ET

Some crucial ingredients for life on Earth may have formed in interstellar space, rather than on the planet's surface.

A new computer model indicates clouds of adenine molecules, a basic component of DNA, can form and survive the harsh conditions of space, and possibly sprinkle onto planets as the stars they orbit travel through a galaxy.

"There may be only a few molecules of adenine per square foot of space, but over millions of years, enough could have accumulated to help make way for life," said study co-author Rainer Glaser, a molecular chemist at the University of Missouri-Columbia.

Glaser and his team's findings are detailed in a recent issue of the journal Astrobiology.

Adenine is one of four "letters" of DNA's alphabet used to store an organism's genetic code. Glaser said the idea that large, two-ringed organic molecules like adenine formed in space may seem outrageous, but current evidence leaves the possibility wide open.

"You can find large molecules in meteorites, including adenine," Glaser said. "We know that adenine can be made elsewhere in the solar system, so why should one consider it impossible to make the building blocks somewhere in interstellar dust?"

Using computer simulations of the cold vacuum of space, Glaser and his colleagues found that hydrogen cyanide (HCN) gas can build adenine. Like pieces in a set of tinker toys, hydrogen cyanide serves as adenine's building blocks; the small molecules bond together into chains and, with a little wiggling, eventually assemble into rings.

Although adenine's first ring needs a tiny energy boost from starlight to form, Glaser said the second ring of the molecule self-assembles without any outside help.

"When you want to have a reaction, you usually need to heat it up," Glaser said. "It's remarkable to find a reaction that doesn't require activation energy. If you do this reaction in space, this is a huge advantage because it takes a long time for a molecule to be hit by a piece of light."

Seasoned for life?

Glaser said adenine's ringed shape helps it absorb and release any excess energy without breaking apart, making it stable enough to form concentrated clouds that planets can drift through.

While getting adenine safely onto a rocky planet's surface is a less developed idea, Glaser said many chemists have barely toyed with the notion that life's basic ingredients formed off of the planet's surface.

"We're at a very early stage of anybody even thinking about these things," he said. "The discussion of life's origin has been highly focused on the idea of a warm pool of liquid on the planet's surface." But Glaser said recent discoveries of planets around distant stars is changing that focus.

"Chemistry in space isn't the chemistry most of us are trained for," Glaser said. "We should take a much bigger approach: Where are all the chemicals in the galaxy and its solar systems, and what can you do with them?"

Antonio Lazcano, an evolutionary biologist at the National Autonomous University of Mexico who has studied life origins for the past 30 years, said Glaser and his colleagues' work is compelling.

"We already know hydrogen cyanide is abundant in interstellar clouds, and it's been suggested that comets can bring some of that material onto planets," Lazcano said. For Glaser and his team's idea to be widely supported, however, adenine needs to be detected in the deep space clouds, Lazcano said.

"The likelihood of detection is very small, but it's still possible," he said. "If astronomers can better eliminate background noise, I think we'll have equipment sensitive enough to detect adenine dust clouds."

[Lazarus Long]

BTW this finding:

Although adenine's first ring needs a tiny energy boost from starlight to form, Glaser said the second ring of the molecule self-assembles without any outside help.

has very important ramifications for nanotechnology.

[Luna]

It's reall ynice to see how it started.
But still hard to imagain how it survived and actually evolved from that simple little organism (was it even an organism back then?)

Other than survival and development, the thing that bothers me with evolution is why only one race can speak?

But I guess it's only because I didn't dig into it yet.

[Lazarus Long]

Other than survival and development, the thing that bothers me with evolution is why only one race can speak?

This is an anthropocentric prejudice more than a fact. It is a residue of the theistic bias that we are somehow separate from the animal world.

Many animals communicate and the higher in intelligence they are, the more organized those communications can be but for humans complex language is a relatively recent phenomenon and a consequence of a convergence of fortunate adaptive characteristics.

My personal argument is that we were a primate with *parroting* (oral mimicry) behaviors that gave our species an adaptive (fitness) advantage. We used it to defend against larger predators and as a lure for smaller prey. As a species we were more like modern chimps and baboons that bonobos. The fossil evidence of the human mouth and its consistent form supports this assertion but does not prove it

Anyway were began at some point systematizing our sound forms with objects as our memory developed and memetic record keeping behaviors evolved. This trend developed into complex language over a period of tens of thousands of years with the most important advances in language being in the last 10 to20 thousand.

However we have found that many species can *learn* language even if they have more trouble forming our words from mina birds to elephants. Complex human language evolved and as it evolved it gave our species more and more of an advantage to rise to the pinnacle of the food chain but it can be looked at as simply a form of evolutionary fitness.

[Luna]

Yeah, sorry I didn't make myself clear enough.
I know animals do communicate, best example is dolphins.

What I mean is that it's strange that no other animal evolved like us and/or no communication between races.

[Lazarus Long]

What I mean is that it's strange that no other animal evolved like us and/or no communication between races.

Evolution is the result of a zero/sum game, scarcity driven environmental economics. There is very little room at the top. As our species came to dominate more and more of all available environmental resources, the *opportunities* (environmental niches) for other species to take those paths by similar or alternative means diminishes.

Also humanity does not tolerate well any competition and we tend to fear and destroy what we perceive to be intelligent competition. Our opportunity to ascend to dominance not merely as humans, but the entire phylum of mammals began in a global cataclysm. It will take such a cataclysm again or our voluntary intervention to uplift additional species, to create the opportunity for other species to join us at the top.

[jenocidal]

investigate Panspermia and Reverse Panspermia.

[AdamSummerfield]

Evolution is the result of a zero/sum game, scarcity driven environmental economics.  There is very little room at the top.  As our species came to dominate more and more of all available environmental resources, the *opportunities* (environmental niches) for other species to take those paths by similar or alternative means diminishes...

Of course, the prime example of this is that we ate and hunted to elimination the other species of the Homo genus such as erectus and neanderthalis once we had emerged from the broth of hominid tribes.

- Sezarus