The Science thread

[DPrinny]

Plus, those moons are really, really chuffing' cold!

Life finds a way
Theres life round volcanic springs in the sea


Also
No news one this?

[crusto]

Sounds interesting. I always wonder how people can be so sure when they say places such as lake vostok are comparable to places they never have or never will see.

[DPrinny]

Maybe they have found something down there, but aint allowed to tell about it...............

[oli_lar]

Could alien life on Europa look like this?

I think that due to gravitational forces, life on Europa could look like this:




What I don't know is whether any of the life on Earth that exists due to geothermal heat as mentioned before always existed that way, or did it evolve from life further up that lived in waters heated by the sun. If so, then maybe there couldn't be life on Europa because that evolution couldn't take place. It'll take 100 years to find out anyway, because the ice is about fifty miles deep and I don't know how they'll break into that. With a hammer, maybe?

All the large animals on them started out in shallow waters. Going by the (sparse) fossil record crustaceans started out in shallow waters as in the Burgess Shale. Obviously there might be earlier crustaceans though, they just haven't been found. I don't know about the micro organisms though, bit of a dull subject!

Lake Ellsworth's ice is 3.4km thick, and they're planning to drill through that in a couple of months. The ice on Europa will be a lot colder (thus harder) and have a lot more stress throughout it, though apparently there are parts as thin as a few km as the surface ice fractures in lines.

[Katzkatz]

Plus, those moons are really, really chuffing' cold!

I thought that Europa was squeezed by Jupiter's gravity(also why it has cracks and ravines on its surface) and that caused friction, and thus heat. Which is why scientists think there could be life inside of it.

[joefish]

Thing is, all these things that live around the thermal vents, the food chain is based on bacteria that get their fuel from the normally toxic chemicals that the vents spit out, and so do not rely on sunlight. What seems to me to be rashly overlooked is that all the multi-cellular creatures from them upwards rely on dissolved oxygen in the surrounding water for metabolising whatever they eat. And the only reason there's sufficient oxygen down there is because of all the plant life in the shallow oceans and on land, which do depend on sunlight. So how it could all kick off if sunlight has never reached any part of the oceans is still not explained.

There may be some simple bacteria-like organisms that can lead a stable existence on whatever chemicals happen to be present, but without the wide spectrum of energy you get from sunlight to drive complex processes like photosynthesis, there's no obvious way to generate oxygen, so there's no good theory on how anything could grow big or particularly active. There really is no substitute for oxygen as a reactant.

[Spector]

Thing is, all these things that live around the thermal vents, the food chain is based on bacteria that get their fuel from the normally toxic chemicals that the vents spit out, and so do not rely on sunlight. What seems to me to be rashly overlooked is that all the multi-cellular creatures from them upwards rely on dissolved oxygen in the surrounding water for metabolising whatever they eat. And the only reason there's sufficient oxygen down there is because of all the plant life in the shallow oceans and on land, which do depend on sunlight. So how it could all kick off if sunlight has never reached any part of the oceans is still not explained.

There may be some simple bacteria-like organisms that can lead a stable existence on whatever chemicals happen to be present, but without the wide spectrum of energy you get from sunlight to drive complex processes like photosynthesis, there's no obvious way to generate oxygen, so there's no good theory on how anything could grow big or particularly active. There really is no substitute for oxygen as a reactant.

On the wiki page there is the following:

"In 1977, during an exploratory dive to the Galapagos Rift in the deep-sea exploration submersible Alvin, scientists discovered colonies of giant tube worms, clams, crustaceans, mussels, and other assorted creatures clustered around undersea volcanic features known as black smokers. These creatures thrive despite having no access to sunlight, and it was soon discovered that they comprise an entirely independent food chain. Instead of plants, the basis for this food chain was a form of bacterium that derived its energy from oxidization of reactive chemicals, such as hydrogen or hydrogen sulfide, that bubbled up from the Earth's interior. This chemosynthesis revolutionized the study of biology by revealing that life need not be sun-dependent; it only requires water and an energy gradient in order to exist.

While the tube worms and other multicellular eukaryotic organisms around these hydrothermal vents respire oxygen and thus are indirectly dependent on photosynthesis, anaerobic chemosynthetic bacteria and archaea that inhabit these ecosystems provide a possible model for life in Europa's ocean.

That quote does seem to suggest it is possible without any photosynthesis directly or indirectly, so there may well be little spacemen jumping about over there right now.

[sscott]

"What are midichlorians Qui Gon?"

[SJ_Sathanas]

It's the sheer scale of everything that boggles my mind. Take the Pillars of Creation nebula. The largest of the three "pillars" is 7 light years long - that's about 42 trillion miles! It's only a part of the Eagle nebula which is 6500 light years away and about 9.5 light years in size.
They reckon it was destroyed by a supernova about 6000 years ago but the light showing the true nature of the region won't reach Earth, travelling at 186,282 miles per second (speed of light), for another millenium.

[joefish]

"While the tube worms and other multicellular eukaryotic organisms around these hydrothermal vents respire oxygen and thus are indirectly dependent on photosynthesis, anaerobic chemosynthetic bacteria and archaea that inhabit these ecosystems provide a possible model for life in Europa's ocean".

That quote does seem to suggest it is possible without any photosynthesis directly or indirectly, so there may well be little spacemen jumping about over there right now.

Um, I hate to go all quotey, but no it doesn't - please read my last paragraph again:

There may be some simple bacteria-like organisms that can lead a stable existence on whatever chemicals happen to be present, but without the wide spectrum of energy you get from sunlight to drive complex processes like photosynthesis, there's no obvious way to generate oxygen, so there's no good theory on how anything could grow big or particularly active. There really is no substitute for oxygen as a reactant.

The point being, and what you've found just backs up, is that we know about anaerobic bacteria (that is, ones that don't rely on oxygen). But they're a bit crap compared to aerobic ones. They're a start, but they're not a sound basis for evolving multi-cellular organisms. So no little green men, just little green goos.

On Earth, photosynthesis came long before any multi-cellular organisms, splitting carbon dioxide from volcanoes into stable carbon for building and pumping out corrosive oxygen as a by-product. Then other organisms cottoned on to exploiting the presence of oxygen to burn fuel and evolved into bigger, more complex lifeforms.

Most animal life on earth, along with car and jet engines, depends on a fuel+oxygen reaction for energy, and assumes that oxygen is always present in the environment. Take away that oxygen and it dies. In fact, give it too much oxygen and it overdoes it and dies too. If oxygen isn't there, you have to carry fuel AND oxygen around with you, like an astronaut in a spacesuit or a rocket engine. Two things which are big, expensive, and cumbersome to reproduce.

There are other options - pairs of chemicals you can carry round for energetic reactions. Hydrogen and chlorine can make a nice bang, but then you acidify any water nearby. But being able to pull one of those in from your environment with very little effort conveys a big advantage.

Now once you've burned that fuel, if something else can't reverse that reaction, you're not going to last long as you choke on your own fumes. And that's where photosynthesis comes in. Those fumes are VERY stable chemicals, and VERY hard to crack back into their component chemicals. Even on an alien world that might depend on other chemical reactions, you'll still have fuel+reactant=energy+fumes, and without sunlight it's hard to see how any natural process could evolve to run in parallel and reverse it.

[Spector]

Um, I hate to go all quotey, but no it doesn't - please read my last paragraph again.

Hey, my name's not Um, it's Spector!

The point being, and what you've found just backs up, is that we know about anaerobic bacteria (that is, ones that don't rely on oxygen). But they're a bit crap compared to aerobic ones. They're a start, but they're not a sound basis for evolving multi-cellular organisms. So no little green men, just little green goos.

On Earth, photosynthesis came long before any multi-cellular organisms, splitting carbon dioxide from volcanoes into stable carbon for building and pumping out corrosive oxygen as a by-product.................

I find your lack of faith disturbing. Once we finally get there (probably the Americans), maybe we'll see something like this:

[sscott]

Hubble Deep Field, 13 billion light years away. That is a long time ago.

The James Webb telesope should hopefully reveal even more - up to a point anyway.

[Mire Mare]

Exciting news from cern tomorrow .. ..

“Tomorrow’s announcement is a result from a 15 year programme to further the frontier of our knowledge. If the Standard Model is confirmed via the discovery of the Higgs boson or whether we need to abandon and start re-writing the text books, it’s a historical day in science that we can all be proud of.”

http://www.iop.org/news/12/july/page_56479.html

[RetroRik]

Exciting news from cern tomorrow .. ..

“Tomorrow’s announcement is a result from a 15 year programme to further the frontier of our knowledge. If the Standard Model is confirmed via the discovery of the Higgs boson or whether we need to abandon and start re-writing the text books, it’s a historical day in science that we can all be proud of.”

http://www.iop.org/news/12/july/page_56479.html

Yep apparently the smaller but much older Tevatron in the US has come up with similar results to the LHC from last year.

The LHC has also done a second test and reproduced the results again.

Mr Higgs himself has been invited today which is causing all the excitement.

I suspect what will be announced is that they cannot actually detect the boson itself but the smoking gun surrounding its existence has been seen. They will be 99% sure the boson exists.

What does it mean for science.? Well it will prove the standard model. Cern will still have a big job to do.
They then need to find out why the very small does not seem to follow the same rules as the very big.

Something Hawkins wants to do before he kicks the bucket.

The scientists at CERN still have years before they are made redundant.

RIK

[necronom]

It looks like they have found it!

Things have mass! Hooray!

http://www.telegraph.co.uk/science/large-hadron-collider/9374788/Higgs-Boson-announcement-from-Cern-LIVE.html