Posted on 08/17/2009 8:26:35 PM PDT by Gordon Greene
The amino acid glycine, a fundamental building block of proteins, has been found in a comet for the first time, bolstering the theory that raw ingredients of life arrived on Earth from outer space, scientists said on Monday.
Microscopic traces of glycine were discovered in a sample of particles retrieved from the tail of comet Wild 2 by the NASA spacecraft Stardust deep in the solar system some 242 million miles (390 million km) from Earth, in January 2004.
Samples of gas and dust collected on a small dish lined with a super-fluffy material called aerogel were returned to Earth two years later in a canister that detached from the spacecraft and landed by parachute in the Utah desert...
...The initial detection of glycine, the most common of 20 amino acids in proteins on Earth, was reported last year, but it took time for scientists to confirm that the compound in question was extraterrestrial in origin.
"We couldn't be sure it wasn't from the manufacturing or the handling of the spacecraft," said astrobiologist Jamie Elsila...
...She presented the findings, accepted for publication in the journal Meteoritics and Planetary Science, to a meeting of the American Chemical Society in Washington, D.C., this week.
"We've seen amino acids in meteorites before, but this is the first time it's been detected in a comet," she said...
...The latest findings add credence to the notion that extraterrestrial objects such as meteorites and comets may have seeded ancient Earth, and other planets, with the raw materials of life that formed elsewhere in the cosmos.
"The discovery of glycine in a comet supports the idea that the fundamental building blocks of life are prevalent in space, and strengthens the argument that life in the universe may be common rather than rare,"
(Excerpt) Read more at reuters.com ...
It depends on the size of the protein molecule. Glycine is C2H5NO2. If you are using the molecular weight of glycine (75) compared to a typical simple protein, say, myoglobin (roughly 18000), the ratio is around 240:1. For more complex proteins the number can be much higher.
AK: Why? There's water all over the solar system, including on Mars. Probably all over the universe.
Can't evos ever discuss what's posted without building a strawman to knock down?
TFM said a water planet LIKE Earth, not just water in our solar system. Mars doesn't even come close to being a watery planet like Earth.
And *probably* all over the universe is nothing but sheer speculation. Unless you have some evidence that gives us reason to believe that there could be planets around the universe with the amount of water on them that Earth has, you're very desperately grasping at straws.
You certainly don't expect us to take your guess as fact, do you? Or even with any kind of credibility?
My point exactly.
So? Water is extremely abundant. The odds of it existing in liquid form are extremely high. In fact, there are almost certainly places in our own solar system where liquid water has existed.
Hundreds. Plus they can only be specific L-amino acids, they have to be in a specific arrangement, with none being out of place, none missing, and none added - if the protein is to function properly.
Of course, it gets a little more complicated when you consider the fact that there are 60,000+ proteins in every human cell.
That's sort of a silly argument, isn't it? Until the mid 1990s, scientists hadn't observed any planets outside of our solar system. Since then, scientists have discovered almost 400 of them. Are there earthlike planets out there? Probably, but it's kind of hard to get there to investigate. We know there are lots of planets and we know there is lots of water. It doesn't take Sherlock Holmes to put two and two together.
No, actually it's not speculation. Water is all over the universe. The Orion nebula alone produces enough water to fill all the Earth's oceans 60 times, EACH DAY!
Source: NASA
You should try learning about this stuff -- it's really fascinating.
Finding water on another planet would be just scratching the surface for the requirements of a planet being capable to sustain complex life.
Yeah, with upwards of several trillion planets that likely exist throughout the the universe, I doubt if another has water.
:o
Find a water planet, complex life will be found there too.
Not seeking a historical trace, or hearing pontifications on presumed odds.
The thing is to find another world like this one.
Find one.
Glycine and several other amino acids are simple to synthesize in the lab or in nature under certain conditions. They are not necessarily associated with life.
You don’t need to go out of the solar system to find an “watery body”. Jupiter’s moon Europa is almost entirely water/ice. Life does exist in extremely cold locations, and below the surface of the external ice there is water... which means at least 33 degrees Fahrenheit. Life exists at our poles where it’s rarely above 33, so there’s no reason to think that underwater life cannot exist on Europa. It may exist there now.
You actually believe that any planet that has liquid water will automatically have complex life on it?
A water planet, with oceans, and lakes, and rivers, like Earth.
I feel quite assured that any such planet is very likely to have complex life.
Do you doubt that?
Water is just one of several requirements for sustaining complex life on a planet. A few more are:
1. A delicately balanced atmosphere that will filter out harmful radiation while allowing in needed radiation.
2. A non-synchronous orbit around its star. If one side of the planet always faces the star, one side of the planet would be in perpetual darkness and extreme cold, while the other side of the planet would be in perpetual light and extreme heat.
3. A moon of the right size and distance from the planet to cause tidal action in the oceans.
4. A magnetosphere around the planet to protect its atmosphere from being whisked away by solar winds.
5. Plant life: to produce photosynthesis; and as a food source (if there were only carnivores, it wouldn't take long for animals to eat themselves out of existence).
These are just a few of the requirements a planet would need to fulfill in order for complex life to exist. In fact, it has been calculated that the chances of a planet like earth could exist are: 1 in 1,000,000,000,000,000. (and that's a conservative figure, btw)
Then you get into the complexities of the origin of life itself. Just the odds for the simplest protein in one cell originating by mere chance are at least: 1 X 10 to the 50th power. Then there are the other components of the cell that are needed for it to function: a protective membrane, cell nucleus, enzymes, ribosomes, different types of RNA, DNA, as well a other components; all needing to be in the right place at the same time for the cell to function.
Just for DNA alone, Bill Gates has pointed out - that just one strand of DNA in one single cell is far more complex than the most complex computer program man has ever devised. Does it sound like DNA could originate by mere chance, and if not, what mysterious, natural force creates DNA?
Find another water planet like Earth and we will see who is right about the likelihood of complex life thriving on it.
Nature is more complex than the most complex computer program.
Why should it be surprising that DNA figures into the extremely complex, intricate, and highly developed patterns of the natural world?
So how do you explain the appearance of DNA and its encoding information?
Was it by "random" bonding of sugars, phosphates and nucleobases? Or were these chemicals bonded together by some mysterious, naturally "directed" process?
The odds would be impossible for the former to be true, and science can even come close to an explanation for the latter.
As to your question, it is not surprising that DNA figures into our complex world. In fact, its a requirement for the existence of life. The question that really needs to be answered is: "If life originated naturally, how do you explain the appearance of DNA"?
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