Are we really alone?

[Winston001]

Do you have a web browser?

Google is your friend.

http://www.google.co.nz/search?hl=en...sed+life&meta=

Ta. Regrettably the links only point to organic bacteria which synthesise sulpher and iron. Fascinating in their own right because they don't need sunlight at all but - still carbon based.

In fact bacteria are found half a mile into the Earths crust happily living in and munching on rock. The point is that carbon forms their molecular structure, not silicon, sulpher or iron.

Maybe I've misread this stuff. Always open to new ideas.

[Skyryder]

Time-travelling bikers? I'm not sure if that explains that whole anal probe thang.

It does if you ride a Guzzi. Guzzi seats are notorious for anal probing.

Skyryder

[onearmedbandit]

Exactly. 10fc.

[Drunken Monkey]

...Maybe I've misread this stuff. Always open to new ideas.

Unlikely, you probably read it right. I just wanted someone else to do the work. As far as I was aware the next likely substance for 'life as we know it - sort of' would be Silicon. I don't think Sulphur can form chains like Carbon or Silicon, so it's unlikely to be able to form sulphur based proteins and other building blocks to create 'life'.

[Wolf]

I saw an amazing demonstration on a science show years ago, they had frozen a scorpion in a block of ice and left it there for around 3 months. On camera they melted it out with a blow torch and as soon as the legs were free they started moving. Once it was able to totally free itself from the ice it scuttled off, seemingly unharmed.

Apparently, when they were testing the early A-bombs out in the desert they sent the investigators into the craters wrapped in protective gear, the geiger counters they carried were going crazy, registering lethal levels of a radioactivity (for a human) - and the area was swarming with scorpions. They surmised they came into the area attracted by the heat of the blast. They captured some and examined them and deemed they were suffering no ill effects from exposure to the radiation.

It is not the only creature on this planet that is so basic (and a scorpion is still fairly complex compared with some) that it can cope with things that would kill us. We all know that the cockroaches will wander out of the coming Nuclear Holocaust wand take over the world.

They'll be sharing it with butterflies and scorpions and many other insects and arachnids.

This is life that evolved here. It is robust owing to its simple nature. Spiders are not disoriented by free fall - they are so small they probably don't know what gravity is, anyway.

There are lifeforms on this planet that could probably survive (given a food supply) if you dropped them on Mars.

Lifeforms that are native to Mars would be even better adapted to survive there. Periods of dormancy during the winter when the water is all frozen, perhaps, or low water requirements to cope with the minimal amount of water available on the planet.

Or there may be trapped pockets of liquid water beneath the surface teeming with life.

The time scale is also interesting. Look at how long the dinosaurs held sway compared with how long we've been here and look at how long they were gone before we came along.

Some of the dinosaurs could have developed language, started using tools, possibly even progressed to farming and building their own structures. How are we to know? We have an incomplete fossil record of the bones of dinosaurs but what would be left behind of a ploughed field? Or even a house made of stone?

What would our greatest cities look like in a few million years if we were all wiped out over the next few years? A few million years of wind and rain, pounding surf, airborne dust, seismic activity...

Even the Great Wall, the only man-made structure visible from space, would be scattered rubble, not even it would survive a couple of million years.

Posit: some of the smaller dinosaurs - say velociraptor sized - herd or pack creatures possibly omnivorous develop enough intelligence to develop language, over time began using tools, went from hunter gatherer to farmer, contriving ways of keeping the carnivores at bay, built villages along the shore.

Then they died with the rest. A few million years of wind, rain and surf there won't be enough left of their villages to recognise - the boulders they shifted into position for housing are now sand. If we're lucky, we have one partial skeleton of this species found protected in the heart of Africa away from the ocean and the destructive surf and nothing special about it that says "tool-maker" or "city builder".

Who would know?

Prove it didn't happen.

Then turn your eyes to the stars - all those worlds that could potentially hold life. For all we know the nearest planets, those whence life might be able to visit without spending generations in cryogenic suspension, are all still on their way back up from their sixth or seventh mass extinction. A planet may have had interstellar travel back when velociraptor was strutting his stuff here and discovered (on airless moons where no erosion can occur) evidence that theirs was not the first race to reach the stars from their own world and then they too followed their predecessors into oblivion. Now, in our time, the new wave of life on their world is only just getting around to the horse collar and the Market Economy. Or maybe it's still simple insect life crawling out of the radioactive wastes of the Great War (for the last species, anyway - there had been others) and nothing yet has risen to fill the niche of dominant life-form.

Wouldn't it be an arse if we finally got a manned expedition to Mars and found a cave with evidence that someone had been there millions of years before us - and instead of a lost race of ancient Martians it turned out to be an exploration team from Earth around the late Jurassic Period.

[Wolf]

Ta. Regrettably the links only point to organic bacteria which synthesise sulpher and iron. Fascinating in their own right because they don't need sunlight at all but - still carbon based.

In fact bacteria are found half a mile into the Earths crust happily living in and munching on rock. The point is that carbon forms their molecular structure, not silicon, sulpher or iron.

Maybe I've misread this stuff. Always open to new ideas.

I read a couple of the pages and it sounds like what I was talking about, I must have misunderstood what the book was driving at - I read it a number of years ago.

It could have been the fact that the life is not reliant on sunlight for energy that was the big departure from "normal life". The "Black Smokers" sound very familiar, so I'm prepared to acknowledge I probably fucked up.

[Wolf]

Wikipedia's bit on Silicon-based life is interesting.

Every time I hear the term I think of an episode of Dr Who (Tom Baker as the Doctor, I recall)

Woman Scientist: What is it?
Doctor: It's a silicon-based lifeform and it's catching up with us.
Woman Scientist: But that's impossible!
Doctor: No it isn't, we're standing still.

[Winston001]

I read a couple of the pages and it sounds like what I was talking about, I must have misunderstood what the book was driving at - I read it a number of years ago.

It could have been the fact that the life is not reliant on sunlight for energy that was the big departure from "normal life". The "Black Smokers" sound very familiar, so I'm prepared to acknowledge I probably fucked up.

No worries and don't be hard on yourself. These are unique organisms and their significance is that they prove that life-forms can exist in exotic locations. Such as under Mars and possibly even on comets. :

[Wolf]

No worries and don't be hard on yourself. These are unique organisms and their significance is that they prove that life-forms can exist in exotic locations. Such as under Mars and possibly even on comets. :

Well, we know Mars had liquid water thanks to the recent probes so that would be a fair indication that there was life of some form on the remote, forbidding planet (sorry, HGW, had to borrow it). Given that some of our insects are too "stupid" to feel the cold and probably have low enough oxygen requirements to exist in Mars' 0.15% oxygen atmosphere even though the pressure is only 1% of Earth's, at least simpler bacteria should have survived on Mars (anaerobic bacteria was once the dominant lifeform on Earth until it polluted itself to the verge of extinction but we still have anaerobic bacteria tucked away safe from the poisonous oxygen.)

Every mass extinction cycle on this planet has had its survivors - anaerobic bacteria, the Tuatara and the Coelacanth. There is no reason to suppose that, had life once flourished on Mars, it is all gone now. The hardier specimens (probably the simplest and those requiring less resources) may well have survived in pockets. The equatorial region would be a good bet but I would not be surprised to find extremely hardy life near the poles because life is so bloody tenacious.

Individuals and sometime species can be fragile things and vanish in the blink of an eye, but life, oh life is tough. It has existed here through searing temperatures, high seismic activity and methane atmospheres, it survived the transition to cooler climes and oxygen atmospheres.

We will never destroy the world or wipe out all life on it. We may render it uninhabitable to us and our stock and our dogs and cats and obliterate every last whale and fish, we can poison the waters and atmosphere, burn the land, poison the soil and render the world so radioactive that even the butterflies die...

And something will come crawling out the other end to a vista of bounty with bugger-all else to compete for food and territory.

Mars a dead world? I seriously doubt it. Nature can't have hit it with anything worst than she hit the Earth and we're here along with survivors of many extinctions.

[Wolf]

Here we go, from nineplanets.org:

On 1996 Aug 6, David McKay et al announced what they thought might be evidence of ancient Martian microorganisms in the meteorite ALH84001. Though there is still some controversy, the majority of the scientific community has not accepted this conclusion. If there is or was life on Mars, we still haven't found it.

We have certainly found enough simple amino acids in meteorites to strongly support the possibility of life as we know it having also formed "out there".

And here is an article bout Cassini's approach to Saturn - it seems that Enceladus may well have liquid water beneath its surface which has prompted speculations about the possibility of life.

If life can exist independant of the sun near the black smokers, it can exist under Enceladus' surface.

"We realise that this is a radical conclusion - that we may have evidence for liquid water within a body so small and so cold," said Dr Carolyn Porco, Cassini imaging team leader at the Space Science Institute in Boulder, US.

"However, if we are right, we have significantly broadened the diversity of Solar System environments where we might possibly have conditions suitable for living organisms. It doesn't get any more exciting than this."

Dr Jeffrey Kargel, from the US Geological Survey in Flagstaff, Arizona, US, believes that shifting, glacier-like tectonic plates and tidal forces could generate and trap heat to produce the activity seen on Enceladus.

His modelling also allows for a deep liquid water ocean saturated with gases such as carbon dioxide (CO2). This CO2 may either be locked up in the icy crust or may exist as an icy clathrate seafloor below the hypothesised ocean.

Other researchers on the Cassini mission say the plume at the south pole may be erupting from near-surface pockets of liquid water above 0C (32 F), like cold versions of the Old Faithful geyser in Yellowstone Park.

"There are other moons in the Solar System that have liquid water oceans covered by kilometres of icy crust," said Dr Andrew Ingersoll from the California Institute of Technology (Caltech) in Pasadena.

"What's different here is that pockets of liquid water may be no more than 10 metres below the surface."

Jupiter's icy moon Europa is also thought to host a briny ocean beneath its crust of ice. Neptune's moon Triton has an icy volcanic surface from which break forth plumes of nitrogen.

All this in one tiny solar system - what else "out there"?

[GSX-RJIM]

If you want to know the truth about other life forms, talk to Surge -he has had personal experance with them.