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Extra-terrestrial life

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Flash
162187.  Sun Apr 01, 2007 5:40 pm Reply with quote

This good stuff comes from Garrick, and may find a home in the Victorian number: how Victorians thought they could communicate with ETs.

Quote:
Q: Born in 1840, Sir Robert Stawell Ball was astronomer to Lord Rosse (the discoverer of the Crab Nebula), the Irish Astronomer-Royal, and Lowndean Professor of Astronomy and Geometry at Cambridge University.

Why did he rule out the idea of communicating with Martians?

A: Because, in his own words, "The necessary flag would have to be as big as Ireland!"

(This wasn't necessarily an insurmountable problem, the problem Ball foresaw was actually waving it).

BACKGROUND: Contacting extraterrestrial intelligence is not a new idea, and in the days before broadcast media Ball's "flag" scheme was not so hare-brained as it now seems.

Other Victorian ET contact plans:
* Karl Gauss suggested drawing the famous Pythagoras diagram on the Siberian tundra, using ten-mile wide strips of planted pine forest as 'outlines' with rye or wheat planted inside the boxes to colour them in.

* French poet Charles Cros spent years trying to persuade the French government to finance the building of a colossal mirror. The plan was to reflect focussed sunlight across space to burn messages in the Martian deserts.

Nowadays, we have SETI - the Search for Extraterrestrial Intelligence - which scours the sky looking for alien transmissions. We have also sent plaques and records in to space, just in case any passing aliens stumble across them.

POSS LINKS:

1) Who would make the worst ambassador to represent planet Earth to aliens?
(A: Former UN Sec-Gen and escaped Nazi Kurt Waldheim, whose greeting on behalf of humanity is carried on the Voyager golden record - see talkboard).

2) The 'Wow!" signal, which I think we covered a series or two back.

Sources:
Ball and the flag:
http://www.geocities.com/ziksby2/Sir_Robert_Ball.html
http://www.freewebs.com/ziksby/
Other proto-SETI ideas shamelessly harvested from: http://en.wikipedia.org/wiki/Communication_with_Extraterrestrial_Intelligence


The question suggested is a bit of a mouthful; better to go with something like "You're a Victorian scientist - how are you going to communicate with ETs?", I would think.

 
Flash
162190.  Sun Apr 01, 2007 5:52 pm Reply with quote

Garrick adds this: Fermi's Paradox.

Quote:
Q: The universe is very big. One paper from 2005 suggests that it may be 78 a minimum billion light-years across, but it may even be infinite. In the portion of the universe that we can observe - a huge sphere centred on Earth - there are an estimated 70 sextillion (7 x 10^22) stars. Some, if not most, of these have planets orbitting around them. From these billions and billions ((C) Carl Sagan) of planets, some will be suitable for some kind life to arise (well, it happened here, which is pretty good proof). Of the lifeforms that arise, we should expect some to evolve intelligence and some of those to set up civilisations, and some of those to engage in interplanetary travel, and some of those to visit earth (which is broadcasting its position with TV and radio signals in all directions, like a lighthouse). And even if none of them were to stumble across us, we should expect the universe to be alive with electromagnetic chatter from communication systems. Sounds reasonable doesn't it? So, panel, your question is ...

... Where IS everyone?

A: There is no real answer to this, it's called the Fermi Paradox, created by Enrico Fermi (the three-word question, supposedly asked by Fermi, is apocryphal but an accurate parsing of the problem).

BACKGROUND: Reduced to its bare bones, it is exactly as outlined above: Why is space apparently so silent and empty when logic and probability alone tell you that it is pullulating with intelligent life?

No-one's going to be able to answer this one (well, probably not anyway, although you never know), but they can have fun trying. Some possible answers for Mr Fry to suggest:
1) "Everyone" is all around us already but using different technologies to communicate, preventing us from detecting them.
2) Our communications systems are too primitive to be detected by "Everyone", so they don't know we are here and therefore don't visit us.
3) We are being deliberately isolated/quarantined for some reason (possibly as part of a wildlife research/conservation program).
4) We got here first and "Everyone" hasn't evolved as far as us yet - somewhere has to be first, so maybe it was us (a sobering thought).

The Fermi paradox can be busted wide open, of course, by assuming that even a tiny percentage of UFO sightings and encounters really do involve genuine extraterrestrials, but there is as yet no evidence to support this.

LINK TO: Drake *e*quation? The preamble in the question has it covered, but if we REALLY wanted to go into details ...

 
Flash
162191.  Sun Apr 01, 2007 6:01 pm Reply with quote

He also links to this, a picture of the 'spiders' (or maybe trees) on Mars http://ida.wr.usgs.gov/fullres/divided/m08046/m0804688a.jpg

Quote:
This image has been overshadowed by the famous 'Face on Mars' nonsense (Which actually could make a question in itself), but was taken near the Martian south pole bythe Mars Orbiter Camera. It shows formations that really do look very much like trees. Incredibly like trees, in fact. But because we know there are no trees on Mars, these cannot be Martian trees. (Cf: Laplace and "There are no stones in the sky, so stones cannot fall from the sky")

Officially, those dendritic-looking forms are geological (sorry, areological) features called 'spiders' that take a radial form in the same way that glass cracks when a projectile passes through it. And yes, the 'spiders' WERE named after the Bowie fantasy.

Arthur C Clarke has come out as a believer in Martian trees but if they ARE trees, they are enormous - up to a kilometre across. But then, Mars has lower gravity and a thinner atmosphere than earth.

The whole thing could have been settled long ago if only the designers of the Mars Orbital Camera had put a 'green' lens in. But as it is, MOC only photographs in red and blue - surely one of explorations most frustrating oversights. SO until a new camera, or a new landing, this question remains open.

FURTHER BACKGROUND
This is just one of many genuine MOC photos that appear to show organic forms in the less hostile areas of Mars. There are plenty of others, showing bush-like structures, something resembling banyan trees, and several which appear to show free water lying in crevasses and ravines. Unfortunately, they mainly feature heavily on woo-hoo websites, which you can look at if you have the patience, but they are the genuine NASA article.

Methane has also been detected in Mars's atmosphere. Since methane breaks down in centuries, some active process on Mars is replenishing it. There are two choices: vulcanism or biological processes.
http://www.astrobio.net/news/article1332.html

There have also been reputable claims that chlorophyll was detected at the landing site of the July 1997 Pathfinder probe:
http://archives.cnn.com/2002/TECH/space/04/05/mars.green/index.html

Arthur C CLarke on the alleged trees:
http://www.space.com/scienceastronomy/solarsystem/clarke_mars_banyon_010709-1.html

But officially, those things in the photo are NOT trees. They are spiders.

Maddeningly enough, we may never get to communicate with a Martian - but only because Martians can't speak or shake hands.

 
Flash
162192.  Sun Apr 01, 2007 6:06 pm Reply with quote

And he goes on:
Quote:

Q: How likely are you to catch a cold from an alien?

BONUS POINTS: Mentioning that the 'flu virus gets its name from the Italian word for 'influence'. Mediaeval astrologers believed epidemics of the deadly disease were caused by the influenza of ill-omened stars.

FORFEIT: "You couldn't because viruses are host-specific" or words to that effect. That's simply not true, as avian flu mutation shows.

A: No-one knows. However, for thousands of years people have believed that you could catch germs from space. It was the firm belief of Fred Hoyle that you not only could become infected with alien microbes, but frequently did, and not only that but you wouldn't be here at all were it not for alien germs.

BACKGROUND: This is the theory of panspermia, formulated by Hoyle and Wickramasinghe, which supposes life to have originated in space and spread to hospitable planets via comets.

Hoyle calculated the amount of time evolution would have taken if it really relied on chance mutations, and decided that you had a better chance of a solar system full of blind men simultaneously solving Rubik's Cube than obtaining a single functioning protein through random combinations. He therefore decided that some other agent was accelerating evolution and decided that germs on comets were the best chance.

It has never been proven, but the threat of space-contamination was taken seriously during the moonlandings, and saw atronauts strictly quarantined after returning to earth.

Hoyle wasn't the only one to believe in panspermia. Greek phiolosopher Anaxagoras first proposed it (as far as we know). It was also revived in modern form by Hermann von Helmholtz (the man who conceived the Heat Death of the Universe).

POSS OTHER BACKGROUND (IF EXANSION IS NEEDED ON THIS): The alleged Martian nanobacteria, terrestrial extremophiles, interstellar radiation.

S: "Lifecloud - The Origin of Life in the Universe" Hoyle and Wickramasinghe, 1978

 
Flash
162194.  Sun Apr 01, 2007 6:13 pm Reply with quote

Last bit:

Quote:
Q: How might the give-away signs be allowing us to recognise if we really lived inside a Matrix-style computer simulation?

FORFEIT: Red pills, blue pills, slow motion, etc.

A: Things might be just a bit too damned neat.

The entire physical structure of the universe relies on six numbers. If they were even marginally different, we couldn't exist.

BACKGROUND: The Astronomer-Royal, Sir Martin Rees, has explored this in his book Just Six Numbers (which I am shamelessly pillaging here, obv) and has drawn from it a very intriguing conclusion.

Given the high number of presumed alien civilisations and the vast age of the universe (see Q2, above) Rees finds it reasonable to postulated machine-based (Or machine-enhanced) intelligences capable of simulating a universe to a very high degree of realism, and certainly sufficient to maintain the illusion to any self-aware subroutine (i.e., supposedly living being) that might exist within that program.

Sir Martin points out that the six consological constants couldn't have been made better for the emergence of life (Sir Fred Hoyle (qv) put it in a more earthy way when he studied the same problem and decided the universe was 'a put-up job').

Sir Martin neither embraces nor refutes the 'Matrix' proposition, but points it out as a very real possibility.

MY TWOPENNORTH: Once you start on that sort of thinking, it's "turtles all the way down". What if the external universe (i.e., the real one that contains our simulation) is also a simulation, and so on? And isn't it just Creationism wearing a labcoat?

LEADS TO SEVERAL OTHER BIG TOPICS THAT I'M JUST GOING TO TOUCH ON HERE:
Anthropic pinciple
Creationism
Cybernetics

BONUS BACKGROUND: Those six numbers in full.
N: strength of the electrical forces holding atoms together, divided by the strength of gravity between them.

Epsilon: efficiency of the strong nuclear force, known to be 0.007. If it was less than 0.006 then hydrogen would not able to fuse into helium and the universe would contain only a thin hydrogen mist. If it was greater than 0.008 then protons would be able to bind to each other directly, so there would be no hydrogen at all.

Omega: the ratio of the universe's actual density to its critical density. If its value was different by 1 in 10^15 parts the physicalk universe would not exist.

Lambda: The strength of antigravity. Not zero but (fortuantely for us) very small indeed.

Q: Relationship between mass and gravitational strength. Any different and we might have had a very thick and lumpy universe.

D: The number of physical dimensions of the universe. More than three and the square law becomes a cube law, meaning nothing will stick together due to weakened attractional forces. Fewer than three and pretty much everything becomes impossible (poss explanation lift from "Flatland"?)

 
dr.bob
162250.  Mon Apr 02, 2007 4:51 am Reply with quote

Flash wrote:
Quote:
The entire physical structure of the universe relies on six numbers. If they were even marginally different, we couldn't exist.


So if they were different, we wouldn't exist and we wouldn't be here to be asking why those numbers aren't any different.

Is that not just a self-selecting case, a bit like Douglas Adams's puddle contemplating the hole in the ground within which it finds itself?

 
ryewacket
162251.  Mon Apr 02, 2007 4:54 am Reply with quote

Great gad, I've made a right hash of the syntax in those haven't I? Apols. That's what comes of working on someone else's Mac (ptou, ptou) and not looking at the screen as I type.

 
ryewacket
162253.  Mon Apr 02, 2007 4:58 am Reply with quote

Quote:
Is that not just a self-selecting case, a bit like Douglas Adams's puddle contemplating the hole in the ground within which it finds itself?


Hard to say, innit. Hence the proposed link to the anthropic principle. If it's a fluke, it's a damn handy one. It's like wondering whether you'd be the same person if your parents had never met.

 
dr.bob
162254.  Mon Apr 02, 2007 5:05 am Reply with quote

Since we're talking about extraterrestrial life:

Q: What's the best indication for life as we know it on a remote planet?

A: An ozone layer

Searching for extraterrestrial life is always going to be fraught with questions about what you define as life (c.f. dodgy episodes of Star Trek) so most people currently dealing with it have decided to make things simpler by looking for "life as we know it", to coin a phrase.

Life on earth requires the presence of liquid water to survive, but water can exist with or without life. The best marker for life as we know it is Oxygen.

Early in our planet's history, living organisms evolved which photosynthesised and converted the CO2 they found all around them into Oxygen. In fact, they were so successful that they were in danger of poisoning their own environment with this new, deadly gas until some other creatures evolved which, thankfully, used the oxygen to generate energy and converted it back into CO2 again.

Oxygen is a highly reactive substance and will not hang around long unless there's a mechanism to replenish it constantly. Currently the only mechanism we know of to create oxygen is a biological one. So, if there's oxygen in the atmosphere, it's a pretty good sign that there's life on that there planet.

Any amount of oxygen will also form a small percentage of ozone (O3). Having a large amount of oxygen in your atmosphere will cause that "small percentage" to become a sizeable amount. So, if you detect ozone in the atmosphere, you can be certain that there's a lot of oxygen on that planet and the probability of life is pretty high.

Ozone has a big advantage over oxygen in terms of detection. It has a nice big, easily identifiable absorption line in the Infra-Red. Looking for absorption lines of oxygen in the visible is hard 'cos there's a lot of visible light coming off the star the planet is orbiting. However, the amount of light given off by the star begins to tail off into the infra-red, whilst the amount of light given off by the planet peaks in the infra-red. So the best contrast between star and planet occurs in the infra-red, which is where the absorption line of ozone happens to be.

Looking for ozone has an advantage over current SETI efforts because it doesn't assume the life has evolved a certain type of communication technology. It doesn't even assume intelligent life. Just life creating oxygen like that on earth. That's why big missions in the future looking for extra-terrestrial life like ESA's "Darwin" mission will be looking for ozone.

 
dr.bob
162255.  Mon Apr 02, 2007 5:08 am Reply with quote

garrick92 wrote:
If it's a fluke, it's a damn handy one.


If the universe is of a fixed lifetime, it may have come and gone billions of times before (whatever "before" means in this context). It may be that this is the first universe where all the elements have been just right, but it may not be an improbable fluke. Just a statistical inevitability given enough tries.

 
ryewacket
162257.  Mon Apr 02, 2007 5:15 am Reply with quote

All true of course. I was being paradoxical.

Quote:
Just a statistical inevitability given enough tries.


"Tries" ...? ;)

Who's that fellow who doesn't play dice, again?

 
dr.bob
162344.  Mon Apr 02, 2007 9:43 am Reply with quote

Flash wrote:
Quote:
Arthur C Clarke has come out as a believer in Martian trees but if they ARE trees, they are enormous - up to a kilometre across. But then, Mars has lower gravity and a thinner atmosphere than earth.


You obviously can't claim something is a tree based on a single photograph.

I wonder what Clarke makes of this photo:



Apparently found in Canada, according to El Reg:

http://www.theregister.co.uk/2006/11/08/google_earth_simulacrum/

The article mentions that no-one can decide is the face is of a Native American or Mayan, but everyone agrees that he's clearly plugged straight into his iPod.

 
ryewacket
162359.  Mon Apr 02, 2007 10:12 am Reply with quote

Quote:
You obviously can't claim something is a tree based on a single photograph.




:) he he

OK, it's a photo that looks like trees. And it's in an area where we know there's subsoil water. On a planet with inexplicably replenishing methane. And a mainly CO2 atmosphere. And inexplicable free oxygen. On which chlorophyll may have been detected.

My point is not to try to use QI to persuade people that Mars has vegetable life (FWIW I'm 70% for and 30 % agin, myself), merely that if the possibility of trees on Mars isn't Quite Interesting, then I don't know what is.

Clarke talks trees:

Quote:
Popular Science - What makes you so confident there is life on Mars?

Arthur C. Clarke - The image is so striking that there is no need to say anything about it -- it's obviously vegetation to any unbiased eye [...]


Of course, if Arthur C Clarke Says So, It Must Be True.

Comparison of trees/martian anomalies:




I love the Mayan, btw. That has to be nicked for an album cover, if it hasn't been already.

Have a nice day, earthling!

 
eggshaped
162511.  Tue Apr 03, 2007 3:28 am Reply with quote

More Mars guff:

Quote:

NAU researchers Glen Cushing and Jut Wynne, working at the U.S. Geological Survey, propose that photos from the Mars Odyssey mission reveal football-field size holes that could be entrances to caves.




Quote:
Martian caves are considered the "best potential havens for life" because they would be protected from surface radiation and other factors, he said.

"We're suggesting that the seven black spots are skylights to areas where the surface may have collapsed into a chamber below," Wynne said. "Preserved evidence of past life on Mars might only be found in caves, and such discovery would be of unparalleled significance."


link

 
dr.bob
162542.  Tue Apr 03, 2007 4:59 am Reply with quote

garrick92 wrote:
:) he he


Git! :)

garrick92 wrote:
OK, it's a photo that looks like trees. And it's in an area where we know there's subsoil water. On a planet with inexplicably replenishing methane. And a mainly CO2 atmosphere. And inexplicable free oxygen. On which chlorophyll may have been detected.


OK, let me rephrase my original point.

You obviously can't claim something is a tree based on a single photograph from space. Certainly not at the resolution of the picture of those martian "trees."

garrick92 wrote:
My point is not to try to use QI to persuade people that Mars has vegetable life (FWIW I'm 70% for and 30 % agin, myself), merely that if the possibility of trees on Mars isn't Quite Interesting, then I don't know what is.


I'm in two minds about this. Yes, the possibility of life on another planet is incredibly interesting. However, where do you draw the line at promoting every crack-pot idea about the possibility of life? Should we get Von Daniken on the phone?

Quote:
Arthur C. Clarke - The image is so striking that there is no need to say anything about it -- it's obviously vegetation to any unbiased eye [...]


Clarke seems to have confused the word "unbiased" with the word "hopelessly uninformed" :)

garrick92 wrote:
Have a nice day, earthling!


What is it with aliens and smiley faces?

Here's the one they found on mars:

 

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