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Saturday, December 19, 2009

Dec. 19 - SA: Life as we don't know it‏

Dear Friends,

Life exists everywhere though it may not be "life" as we know it...

Be Well.


SA: Life as we don't know it

Postby Theboss on Thu Dec 17, 2009 3:28 pm

It is definitely worth considering that other options do exist besides water and carbon. Alternative biochemists speculate that there are several atoms and solvents that could potentially spawn life.

Carbon is the molecular glue of life, just add water and you’ve got life. Well, it’s not that simple but it does give a good general idea. The carbon/water combo even worked so well that we have trouble imagining anything else. But it’s definitely worth considering that other combinations exist besides carbon/water. There are many speculations about atoms and compounds that could potentially spawn life, in this article I will cover two of these compounds.
The first and most plausible carbon replacement is silicon.
Silicon was first mentioned as a base for life the by the Brittish chemist James Emerson Reynolds in 1893, in his opening address to the British Association for the Advancement of Science, He stated that because of the heat stability of silicon compounds might allow life to exist in very high temperatures. Comparable life would be the thermopiles, microbes that can live in temperatures from 40 to 113 degrees centigrade. So to our eye’s these life forms would be extremophiles, living in places that would be too hostile for any carbon based life.

Silicon is a likely candidate because it is very common in the universe and lies directly under carbon in the periodic table of elements, meaning that it shares much of it’s basic chemistry. For example carbon can form Methane(CH4) and Silicon can form Siliane(SIH4). Both elements can also form long chains, or polymers, which in fact are the building blocks of life. So theoretically silicone DNA could exist, since its stable enough.
There is tho, one possibly fatal characteristic to silicone based life, namely the way it reacts with oxygen. Where carbon reacts to the gas carbon-dioxide(CO2) silicone becomes Silicone-dioxide(SiO2) , a solid substance. So where CO2 is easily removed from the body SIO2 is not. Disposing of such a substance would pose a major respiratory challenge.
Silicone life is often depicted as a living rock or crystal, for example H. G. Wells wrote:
One is startled towards fantastic imaginings by such a suggestion: visions of silicon-aluminium organisms – why not silicon-aluminium men at once? – wandering through an atmosphere of gaseous sulphur, let us say, by the shores of a sea of liquid iron some thousand degrees or so above the temperature of a blast furnace.
As the silicone based life forms are nothing like us they still share one crucial factor, they are dependant of water for their biological processes. But the next possible life forms are not.
These life forms would go by the name of ammonia-based life.

This possibility was first suggested in 1954 by J. B. S. Haldane, speaking at the Symposium on the Origin of Life. He suggested that water could be replaced as a solvent by liquid ammonia(NH3).
Part of his observation was based on the behavior of ammonia, which behaves very similar to water only in lower temperatures, for example methanol( CH3OH) and it’s ammonia counterpart, methylamine( CH3NH2).
In fact ammonia can replace water in nearly all compounds found in terrestrial life. Making it hardly inferior to water. In fact there are probably as many different possibilities in carbon-ammonia as in carbon-water systems.
This suggests that life on ammonia-rich worlds such as gas giants (e.g. Jupiter) would be very possible without even a drop of water on the whole planet.
Liquid ammonia does have some striking chemical similarities with water. It is intact even better in dissolving organic substances then water. The main objection is that the liquid range of ammonia is -44 degrees centigrade and that that is too low for any life to thrive. This true but the liquid range is specified by the pressure of the planet which on earth is 1atm but for example on Jupiter or Venus where the pressure is 60atm the boiling point is ammonia becomes 98 degrees centigrade instead of minus -33 giving it a liquid range of 175 degrees meaning that ammonia based life doesn’t need to be low-temperature life at all!
A downside to ammonia based life is the way that its dissociates, or lets molecules fall apart into positive and negative ions. This prosess is crucial for acid-base reactions. In ammonia the positive ions would be the NH+ ion, being a very strong acid and deadly to life as we know it. But scientists do suggest that ammonia-based life forms may use other salts to regulate their functions than we do.

Also there is the problem of the density of ammonia, being almost identical to water it has still one flaw that pose a major restriction to the life, namely it’s solid form does not float on the liquid form like in water. In fact water is the only substance known to man where the solid is less dense then the liquid. The reason that this is a major problem is because this would mean that any ammonia-ice that would form would sink to the bottom of the liquid, flattening all life. Ice is also a good insulator, so while floating it keeps the water beneath at a constant temperature making is virtually impossible to freeze all the water. But when the ice sinks then it loses all its isolative properties and allows the water to freeze leaving no place for the life to evolve.
This would restrict the life to a planet where the temperatures are well above the ammonia freezing point for it to be a potential candidate for a water replacement.
Regarding these facts ammonia-based life would have the largest chance of forming and surviving on a hot planet with high pressure. If we combine it with silicone-based life then the chances of its forming would grow because silicone works well at high temperatures. Also the biological properties of these two substances would allow for an even more efficient way of photosynthesis and dissimilation.
Instead of O2 these life forms would breath H2, this seems catastrophic because hydrogen is very flammable but this is only the case in an O2 rich environment, if the atmosphere is actually mainly H2 it is in fact very stable. These life forms would thrive on gas giants like Venus and Jupiter

In this article we have only covered two of the large number of combinations and this leaves us with but one question; Are we looking in the right places? The SETI program specifically searches for earth like planets with water and oxygen and completely ignore all other possibilities . With the gigantic number of planets and a with different compounds, pressure and atmospheres it is very possible that other forms of life have evolved where carbon-based life would not stand a chance.
It’s even not beyond the realm of possibility that our first encounter with alien life will not be a carbon-based life form.

This article and all its contents are copyright 2009-2010. All rights reserved.

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How to Digitally Record/Video a UFO sighting:

Como registar digitalmente ou gravar um vídeo de um avistamento de um UFO:

Stabilize the camera on a tripod. If there is no tripod, then set it on top of a stable, flat surface. If that is not possible lean against a wall to stabilize your body and prevent the camera from filming in a shaky, unsteady manner.

Estabilize a camera com um tripé. Se não tiver um tripé, então coloque-a em cima de uma superfície estável. Se não for possível, então encoste-se a uma parede para estabilizar o corpo e evitar que a camera registe de maneira tremida e instável.

Provide visual reference points for comparison. This includes the horizon, treetops, lampposts, houses, and geographical landmarks (i.e., Horsetooth Reservoir, Mt. Adams, etc.) Provide this in the video whenever is appropriate and doesn’t detract from what your focus is, the UFO.

Forneça pontos visuais de referência para comparação. Isso inclui o horizonte, cimo das árvores, postes de iluminação, pontos de referência geográficos (como o Reservatório de Horsetooth, Mone Adams, etc) Forneça esses pontos no vídeo sempre que for apropriado e não se distraia do que é o seu foco, o UFO/a Nave.

Narrate your videotape. Provide details of the date, time, location, and direction (N,S,E,W) you are looking in. Provide your observations on the weather, including approximate temperature, windspeed, any visible cloud cover or noticeable weather anomalies or events. Narrate on the shape, size, color, movements, approximate altitude of the UFO, etc and what it appears to be doing. Also include any unusual physical, psychological or emotional sensations you might have. Narrate any visual reference points on camera so they correlate with what the viewer will see, and thereby will be better able to understand.

Faça a narração do vídeo. Forneça pormenores sobre a data, hora, local e direcção (Norte, Sul, Este, Oeste) que está a observar. Faça observações sobre as condições atmosféricas, incluindo a temperatura aproximada, velocidade do vento, quantidade de nuvens, anomalias ou acontecimentos meteorológicos evidentes. Descreva a forma, o tamanho, a cor, os movimentos, a altitude aproximada onde se encontra o UFO/nave, etc e o que aparenta estar a fazer. Inclua também quaisquer aspectos pouco habituais de sensações físicas, psicológicas ou emocionais que possa ter. Faça a narração de todos os pontos de referência visual que o espectador irá ver e que, deste modo, será capaz de compreender melhor.

Be persistent and consistent. Return to the scene to videotape and record at this same location. If you have been successful once, the UFO sightings may be occurring in this region regularly, perhaps for specific reasons unknown, and you may be successful again. You may also wish to return to the same location at a different time of day (daylight hours) for better orientation and reference. Film just a minute or two under “normal” circumstances for comparison. Write down what you remember immediately after. As soon as you are done recording the experience/event, immediately write down your impressions, memories, thoughts, emotions, etc. so it is on the record in writing. If there were other witnesses, have them independently record their own impressions, thoughts, etc. Include in this exercise any drawings, sketches, or diagrams. Make sure you date and sign your documentation.

Seja persistente e não contraditório. Volte ao local da cena e registe o mesmo local. Se foi bem sucedido uma vez, pode ser que nessa região ocorram avistamentos de UFOs/naves com regularidade, talvez por razões específicas desconhecidas, e talvez possa ser novamente bem sucedido. Pode também desejar voltar ao mesmo lugar a horas diferentes do dia (durante as horas de luz)para ter uma orientação e referência melhor. Filme apenas um ,inuto ou dois em circunstâncias “normais” para ter um termo de comparação. Escreva tudo o que viu imediatamente após o acontecimento. Logo após ter feito o registo da experiência/acontecimento, escreva imediatamente as impressões, memórias, pensamentos, emoções, etc para que fiquem registadas por escrito. Se houver outras testemunhas, peça-lhes para registar independentemente as suas próprias impressões, pensamentos, etc. Inclua quaisquer desenhos, esbolos, diagramas. Certifique-se que data e assina o seu documento/testemunho.

Always be prepared. Have a digital camera or better yet a video camera with you, charged and ready to go, at all times. Make sure you know how to use your camera (and your cell phone video/photo camera) quickly and properly. These events can occur suddenly, unexpectedly, and often quite randomly, so you will need to be prepared.

Esteja sempre preparado, Tenha sempre uma camera digital, melhor ainda, uma camera vídeo consigo, carregada e pronta a usar sempre que necessário. Certifique-se que sabe como lidar com a sua camera (ou com o seu celular/camera fotográfica) rápida e adequadamente. Esses acontecimentos podem acontecer súbita e inesperadamente e, por vezes, acidentalmente, por isso, necessita estar preparado.

Look up. Be prepared. Report. Share.

Olhe para cima, Esteja preparado, Relate, Partilhe.



Pf., clique no símbolo do YouTube e depois no quadrado pequeno, em baixo, ao lado direito para obter as legendas CC, e escolha PORTUGUÊS

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NGC - UFO's in EUROPE (Porugal included)

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