Building Blocks of Life Found in Planet-Forming Disk

space.com ^ | 12/20/05

[KevinDavis]

he basic molecules of life are scattered through the universe, collecting in faraway galactic clouds, on passing comets and asteroids, and on the planets here in our solar system.

But scientists still don’t know how these molecules came to be, or how they originally came together to form life. Now, for the first time ever, astronomers have found some of the basic compounds necessary to build organic molecules and proteins found in DNA within the inner regions of a planet-forming disk.

“We see prebiotic organic molecules in comets and the gas giant planets in our own solar system and wonder, where did these chemicals come from?” said Marc Kassis, support astronomer at the W. M. Keck Observatory. “The Spitzer Space Telescope is letting us study these young stellar objects in new and revealing ways, giving us exciting clues about where life may form in the universe.”

The object—IRS 46—is located in the Milky Way galaxy, about 375 light years from Earth, in the constellation Ophiuchus.

[KevinDavis]

A potential for a new Earth to be formed. It is a matter of time we find a Earth like planet...

[KevinDavis]

[brytlea]

Can someone explain to me how they can discern these things from this far away? I don't understand how they do that.
susie

[msf92497]

I'll buy into it when they start seeing ATM's spontaneously assembling. I mean, it's an infinite universe, isn't it???

[DoughtyOne]

I'm not able to do the topic justice, but certain colors provide clues to chemical compositions. Perhaps someone can expand on that for you.

[Simo Hayha]

Can someone explain to me how they can discern these things from this far away?

I suspect they'd say they study light to discern what is distant. Either that or Marvin the Martian filled them in after he vaporized Bugs Bunny with his Illudium P-46. Wouldn't you love to come back 500 years from now to discover we were wrong about so much that we are so certain of today?

[minus_273]

add me to the space ping :)

[burzum]

I'm not going to into full detail on this as that would take a course in quantum mechanics, but I'll give you the basics. The process used is called light spectrography.

The key concept to understanding how light spectrography is the quantum energy levels of the electrons that are bound by an atom. Consider an atom of hydrogen where one electron is bound at some energy. The electron is not free to go in a straight path due to the electrical attraction by the proton in the nucleus. But the electron will still have some kinetic energy as it moves around the nucleus. Quantum mechanics predicts that the kinetic energy can never be zero (in which case the electron would be at the same location as the proton), and exists in discrete energy levels. If a photon (electromagnetic radiation, i.e. light) hits the electron a few things can happen. If the light has the same energy as the difference in discrete energy levels, the atom will absorb that light. This will increase the kinetic energy of the electron. In an alternate (and perhaps the same) case, if an electron is excited to a higher energy level, it can drop down to a lower energy level by emitting a photon.

What you get from this is spectral lines (a certain frequency of light since the energy of a photon of light is proportional to its frequency). Either a spectral line is missing (like the sodium lines from the sun) indicating that some specific element is absorbing light before it gets to you, or in certain cases you only receive the spectral lines of emission. Each element has very specific spectral lines which indicate that it either absorbed light or emitted light on its way to you.

There is a huge amount of information that I have left out, but this technique can be used in any bound system, not just that of a hydrogen atom or other elements. Molecules also change the bound energy of the electrons in them so they will have specific spectra.

[minus_273]

if i remember my courses in college, each chemical will absorb and release energy (say light) in a unique way. If you know what the pattern should look like for a certain chemical you can identify it when you see that pattern coming from space.

One of the tests we did was look at light coming into boston from the sun. It showed a large amount of mercury in the air.

[luvbach1]

right. spectrography

[Mike Darancette]

I mean, it's an infinite universe, isn't it???

I love the term "Building Blocks of Life", I guess that means that given time and chance they will come together to make life as we know it.

Let's give it a big head start, I'll set out a ham sandwich and see how long it takes to evolve into something that can do the calculus.

[RightWingNilla]

ping

[balch3]

those nutty Darwinists will fall for the most farfetched tall tales.

[emiller]

The building block for life is a low-interest loan.

[dangus]

I firmly believe in evolution, but for the second time this week, I have to call the so-called science reports, "bullsh!+." There is nothing spectacular about the presence of organic compounds. The question is how do you go from nucleotides to DNA.

[dangus]

HYDROGEN CYANIDE? What a load of BS!

[SunkenCiv]

panspermia:

Google

[RobbyS]

Oh? When we gain the powers attributed to angels. Cynano wrote a play about a trip to the moon accomplished by balloon travel. I gather that any space travel will remain as virtual as his imagined journey.

[HOTTIEBOY]

Yeah, it is alot easier to believe an man who wrote a book 2000 yaers ago that said an entity snaps his fingers and everything we know came into existance than it is to believe an astro physisist from M.I.T.



Sarc/off

[Paradox]

Do you know the exact details by which He works his miracles? Behold his handiwork.