Just wonder how different the life there in space compared to our life here on earth.

Is there any possibility that there's a planet identical with our planet earth?
You may share any idea or comment.
thanks in advance.

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One Earth, One Sky - IYA 2009
All moderation in purple

It will be different, as it will have to adapt to environments that are different to ours. How different? Well, look at Earth. We're already living with 'aliens'. There are so many different types of life here on Earth that they may as well be from another planet. Think of all the different forms: snakes, elephants, porcupines, lobster, sharks, stick insects, butterflies, oak trees, bacteria, viruses, earthworms, peacocks, lamprey, bees, etc, etc.

If you knew nothing of life on Earth, how would you know if any one of the above was a native of Earth and not some other planet?

Identical - no. Similar - in terms of size, composition and temperature range, yes. Any life that evolves there, would face similar challenges that life faced on Earth. These include finding a source of energy (food), competing with other lifeforms, adapting to conditions, reproducing, etc.

There would be broad similarities to life on Earth, depending on the environment that they live in. For example, purely aquatic creatures tend to be streamlined and flexible to better navigate through water. The environment shapes the animal and similar environments may produce similar body plans (even if the underlying physiology is totally different, eg dolphins look similar to sharks - both adapted to live in water, but are totally different animals).

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Conscious reasoning is an attempt to justify the choice after it has been made.

As you say, so many forms of life already look alien and have "alien" forms of living -- ways that were not imagined until that organism was found, like rock metabolizing bacteria or life in ultra hot deep ocean vents.

I think the basic question is whether any alien life would be non-carbon based and use means other than DNA/RNA to perpetuate copies of itself. But even if carbon-based, DNA/RNA utilizing life is universal, the question still remains of whether it is related to Earth life or not.

Yes, this is not known.

Also, they are still not sure of how life started on earth, and so it's hard to get the details of how life started on other planets and what form it took.

Life may be very different on some worlds, or reasonably similar to Earth-life on others. One interesting idea I've heard is the possibility that life floating in the atmosphere of a gas giant may have cells filled with gases rather than with liquids- this would make the creature lighter, but it would need to have an entirely different type of metabolism to liquid life.

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I can't imagine why you'd need anything stranger than what we've got here.

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Where mainstream ideas can't be found,
some novel theories can be had.
But keep your feet both on the ground;
Sometimes the astronomy's bad.

You may see the cosmos through the noise,
But take care which path you choose.
Remember when reading conspiracy ploys,
A mind's a terrible thing to lose.

So keep your spider sense on high
And before they drive you to booze,
Take time to roll up your pant legs, boys,
It's too late to save your shoes.

Depends on what you mean by 'related'. Biochemically it would be different, I'm sure, but if broadly similar environmental conditions exist, then it's likely that the creatures too might have similar morphologies. For example, I'd be very surprised that if in such an environment there weren't creatures that resembled snakes/eels/worms.

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Conscious reasoning is an attempt to justify the choice after it has been made.

You're sure that alien life would not be carbon based, DNA/RNA utilizing organisms?

There are some excellent reasons why extraterrestrial life will very likely be organic - carbon chains and water.

Remember that the periodic table is universal. Every planet everwhere in he universe, regardless of how hot or cold or wet or dry, has a fixed set of atoms to work with. Only a very few of those do anything interesting. Water and carbon do some extremely interesting things that are virtually unique in the chemical world.



This is not to say carbon chains and water is the only way life could form, but it is very likely to be what we encounter. (Think of this: you are walking on a pebble beach. 999 out of every thousand pebbles is white, the thousandth is black. There's a possibility that you'll pick up a black pebble, but it is far, far more likely that the first few hundred pebbles you pick up will be white.)

I didn't mean to imply that necessarily. I agree with DaveC426913 about which chemical elements are most likely to form complex bonds and structures, ie carbon based. And there may well be a molecule similar to RNA/DNA, but it may not be necessary. Even iif there is an analogue, it would likely have a different structure and use different chemical bases to the four that are used on Earth.

Scientists have already experimented with different chemical bases, up to twelve (compared with the usual four A, T, C and G) and have shown that self replicating molecular machinery can work with them. See this report.

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Conscious reasoning is an attempt to justify the choice after it has been made.

I wonder if somewhere out there are creatures whose body can produce fire. For some reason we don't have any here. I guess bombardier beetle come closest.

It would be effective and novel tool for catching prey and for self-defend.

But would it be worth enough to be worth it for the cost? Fire is pretty energy intensive,and life as we know it is mostly water, not exactly stuff that burns well. Irritating chemicals and poisons sound like a better option, in my opinion.

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Hmmm... that's right. But if your enemy is furry it might catch fire. Or if you try chase something out of it's nest/hole fire might do it. Or on plains fire could be used to prevent prey from escaping.

Imagine a flatulent cow with a flint-like patch and a striker under its tail. A single muscle contraction could make a spark in time to ignite a burst of methane. Not too energy intensive.

As a matter of fact, maybe we want to engineer cows that burn the methane they produce to reduce their impact on global climate change. Of course that could cause other problems.

Sprakles by "moving parts" might be a bit difficult as it requires so hard materials. But it is well-known fact that some animals can produce high voltage electricity. So I could imagine an organ that produces a short circuit and as a result sparkles (maybe even flames could be possible). That combined with a suitable gas would do.

I wonder could species living underwater develop a technological civilization. I guess the crucial question is would they dare to enter land. I guess it wouldn't be so complicated to develop a crude waterproof suit filled with water that would allow them to take first steps on land. That might lead to better suits so they could finally invent things like fire, metallurgy and so on. But if their planet would be completely covered with sea it might be next to impossible to develop metallurgy, which probably is mandatory if you want to build something we consider advanced. Although even in that case, if they were smart and industrious enough they might try to build artificial islands.

I am imagining it, and frankly it doesn't sound very useful. It produces a momentary jet of flame. At most that will scare away some predators temporarily,and it would be hardly lethal or irritating. In the time between the time it takes to regenerate the methane, the predators can gobble it up. As well, if it were any more effective, it might cause a brush fire, which could kill the creature and it's relatives, taking the 'fire starter' genes out of production.

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Maybe not the best defence for a cow, but going back to the original question, it doesn't seem impossible or even impractical that an organism could develop a methane producing organ and a spark producing organ to use flame in one way or another. (The intelligent design people would have a field day with that idea!)

But what about my plan for genetically engineered, methane burning cows to save the planet from climate change catastrophe?


(Yes, Teemu L, introducing some electric eel genes would probably be better than trying to come up with a "flintlock gene". Maybe we could outfit cows with sparking prosthetics in the meantime.)

if anything that would provide evidence for their case as it has not only no purpose, for reproductive gain or pleasure, it just uses up resources. Evolution is often a compromise. How good would a rectal flame thrower be as a rectum? Engineering is quite another thing thing. They are working on goats with some spider genes to produce spider silk in their milk. From a survival perspective, it's quite useless, but it's being engineered in for a human purpose. So just because we could in theory produce flint and flatus flocks doesn't mean it could happen from an natural selection perspective.
It would produce carbon dioxide, which is a relatively weak greenhouse gas, and water vapour, which is a very powerful greenhouse gas.

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I once sat on a caterpillar that the locals in India called a cumberlie puchi, means fire insect.

It felt like someone was holding a burning candle under my upper thigh for 2 weeks. Such a small furry gorgeous insect as well, I had no idea it was so poisonous.

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"If you've made it to retirement without being blamed for a major disaster, you've failed as an engineer."

Often that prettiness is a big clue, as the creature no more wants to be eaten, then you want to be poisoned. So it will advertise that by wearing bright colours so birds and other predators can distinguish it from other,non poisonous, species. Another example of warning colouration is the quite beautiful Poison Dart Tree Frogs.
Of course, this can and does lead to 'false flag' fakers, who have bright colouring resembling poisonous species, but are in fact harmless to eat.

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For the record, comparatively little methane is ejected from a cow as flatulence. The bulk of the methane is belched.


"Cattle emit a large volume of methane, 95% of it through eructation or burping, not flatulence."
http://en.wikipedia.org/wiki/Cattle#...nmental_impact

"Cows don't emit 400 quarts of flatulence a day. According to Professor Johnson, they emit 400 quarts' worth of burps, known in polite circles as eructation. "
http://www.straightdope.com/columns/...ths-atmosphere

"Cows emit a massive amount of methane through belching, with a lesser amount through flatulence."
http://animals.howstuffworks.com/mam...ethane-cow.htm

I don't think we are in a position to compare life out there with anything on Earth, as we are yet to encounter any aliens. So for now we'll have to rely on science fiction to make the comparisons for us.

I guess I disagree with that. I don't consider myself a science fiction writer but dispite of that I can try to imagine what kind of life is possible and what is not. I think as a result of imagination, reasoning and conversation I can at least make assumptions like "this and this kind creature doesn't sound credible" or "if life really is a commonplace in universe then somewhere out there probably is that kind of creature". It might not be science but at least it's fascinating.

We have plenty of science at hand. Again, we know perfectly well that they will be made of some set of the same 92 elements we have here on Earth. We know pretty well how those elements tend to behave together - what ones combine, what ones do not.

And we know some of the requirements for what we're looking for in terms of complexity.

If we did nothing else but list sets of atoms that were capable of forming complex molecules, the list would be quite short.

Hi all

There is a very intresting book by Simon Conway Morris called ' lifes Solutions' which covers the theme of convergence and its implications for life on Earth and possibly throughout the Universe. Its very relevent to the topic being discussed.

Regards

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singlebraincell

Epsilon Delphinus

Beings of Light....
Our target is in the area of The Tail of the Dolphin.

It is a gas giant like Jupiter, but the exact size of our sun. It is unremarkable except it glows soft beige. It has a moon, which has a moon, which is all-deceptive because our beige planet is in actuality a star!

To begin with the moon is really the burnt-out companion of our gas giant. A blackened crystal. Around this circles an asteroid that is a conglomerate of stones. All illuminated by starlight.

To understand better we must enter the "Beige Star". At its center is a clear crystal twice the size of earth that emits white light without heat. This is a crystalline star being who illuminates the gaseous sphere around it with its consciousness.

All life here exists in a gaseous state. "The Children of the Sun" are wisps of sentient matter. When an earth-er inquires them they respond by assuming a human shape with arms and hands, to be polite.

They do not speak, rather they just show you, and then you get the idea.
Their existence is in the breath of the Star-crystal, where crystalline cathedrals float on cloudbanks of sky-blue obsidian, buoyant on gasses of incredible composition.

The web of life existing as a mist upon a landscape of gray-velvet clouds in majestic repose before a distant horizon of dark beige below and light above.
The Children of the Sun took me to meet their mother.

The Star-crystal Entity at the center of it all. It split open revealing itself to me from the poles, and as it did this the same thing happened in my heart. She said, "Welcome" and the love of the galactic consciousness filled me to rapture. When that happens Valkyrie cry.

She told me the burnt out crystal in her orbit had been her companion, like herself supporting a gaseous biosphere as an expression of divinity, but one day suddenly ignited in a flash that intensified the brightness of the Milky Way Galaxy for 1000 years earth standard time. The atmosphere coalesced into the rocky asteroid that now orbits the ex-pent star-crystal.

I asked her if she was lonely for her companion. Do you know what she said?
"Yes Michael, but just as Cindy is still there for you, and helping you to cope and hang on my companion is still here with me, and just as bright, or even brighter then ever! Do you know why that is, Michael?"

I kind-of did know, but I wanted to hear her say it, so I asked, "Please tell me?", and she said, "Stars go to Heaven! The Heaven beyond Heaven....
The Great Beyond where even our Creator will go when she/he is done. The Eternity Beyond Eternity."

This was too much, and I broke down and sobbed with such joy, and sorrow, and confusion, and understanding that I found the Nirvana in Suffering. An Epiphany of the realization that I couldn't realize anything, and I was so ignorant I did not know anything.
I finally knew that I did not know.
That was when I suddenly found myself at a computer terminal typing words that could not express the meaning of what I was trying to communicate, and I posted it here.


This next one actually happened,

Late October of 01 I am driving my younger daughter to school.
We lived in the rural Ozarks.
The Sun was rising but not over the eastern ridge of hills. In the Horizon was a fiery cloudbank that stretched from where the sun was rising to the south.

In the clouds, edge on leaning toward us was a huge swirl of orange fire, like a burning galaxy, spiral arms and all.
At the end of each spiral arm was an orb that contained a small "Fiery Galaxy" one on each end and the whole thing was rotating slowly.
It seemed to be effecting the atmosphere somehow.
We stopped and looked at this in awesome wonder.
We then noticed the same phenomenon was occurring further away in the cloudbank to the south.
I drove my daughter to school. We both agreed we had witnessed something profound.
That evening on the local ABC affiliate, There was a shot of that sunrise, taped by the station weatherman on his way to work.
The News Anchor asked "What was that?" when the shot went from a close up of the phenomena to a view of the whole sky, and you could then see the second one in the distance as well.

The news anchor then said ignorantly "Oh it's just the sunset".... And he went into a segeway for sports.

I know now we saw the Delphinians. The Native Americans know them as the Thunderbeings. They have been doctoring the atmosphere of the planet. They come from that star I described.
They call themselves "The Children of the Sun" very correct since they live in the outer atmosphere of a cold star! They are beings who glow from within, Illuminated by collected starlight they store inside themselves.

They run on starlight!

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osiris

I'll have what he's ^ having!

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Conscious reasoning is an attempt to justify the choice after it has been made.

Conway Morris' book has been discussed here in the past. I have great respect for him, but I suspect that he is wrong if he expects to consistently find familiar forms on other life-bearing planets.

Convergence happens on our world mostly between species which are distantly related; we will share no genetic material whatsoever with life-forms on other worlds, so we can't expect them to resemble Earth-life very much.

I also suspect, but can't prove, that the range of life-bearing habitats in the universe is much wider than those found on Earth, and the solutions that life finds to the problems of living in such worlds will be very different to the solutions found on our planet.

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New Orion's Arm Site . The Starlark . Against a Diamond Sky (OA Novella Collection) . OA Flickr set