PDA

View Full Version : Life in the universe



g99
2003-Feb-08, 01:52 AM
I am taking a class on Life in the universe right now. It is a sophmore level class, so it only skims the surface. (you might wonder why a senior in college is taking a sophmore level class. Well because it looked really fun. It is. /phpBB/images/smiles/icon_smile.gif)

But we were talking about the common origin of all life on earth. Some of the facts that show our common origin is that we all use the same 20 Amino acids, Code for the same Amino acids and the same DNA Triplet code, and all use ATP for energy.


Now that we got that down, What are the chances of some other place forming the same Amino acids and using ATP? Are they naturally going to form that way? or did they happen to form that way?

Also we have found live near thermal vents in the deep oceans, on ocean riges, and other very inhospitable places. Could life live in space? Could a bacteria make a cell wall thick enougth or find some way to counter the radiation and harsh cold of space?
For example. Could the Bacteria (or some eukaryote) develope a "gas bag" full of ozone to filter UV rays and have water vapor or CO2 to absorb infared radiation to keep the cell hot enougth for chemical reactions to form?

zwi
2003-Feb-08, 02:23 AM
Also we have found live near thermal vents in the deep oceans, on ocean riges, and other very inhospitable places. Could life live in space? Could a bacteria make a cell wall thick enougth or find some way to counter the radiation and harsh cold of space?
For example. Could the Bacteria (or some eukaryote) develope a "gas bag" full of ozone to filter UV rays and have water vapor or CO2 to absorb infared radiation to keep the cell hot enougth for chemical reactions to form?
_________________


g99

To me it goes without saying, almost as an axiom, that the universe is pregnant.

Life doesnt have to be exactly the same as it is here, but will use certain aminoacids, sugars, phosphates

The right kind of chemicals has been found in carbonaceous chondrites, undersea vents, and molecular clouds such as Barnard 68

You dont need to becloud the issue with the concepts of eukaryotes or prokaryotes

Zwi

<font size=-1>[ This Message was edited by: zwi on 2003-02-07 21:24 ]</font>

g99
2003-Feb-08, 02:33 AM
huh? I am sorry but i am confused about your post.

I was just pondering how life would work on other places and what if there is a chance it could be like life here or completely different. Thne i was asking how life could live in space.

I believe there is life otherplaces, but i just wonder what it is like.

JS Princeton
2003-Feb-08, 07:39 AM
Well, g99, life is probably the same and different. We really don't know at this point more than that. Of course, you might be a panspermist (http://www.panspermia.org), but that is an opposing mainstream opinion. I'm fairly certain that the ISM dust is NOT freeze dried bacteria. If you aren't convinced, we might have it out in the other forum.

In terms of radiation damage, we have now observed bacteria that can withstand incredible amounts of radiation and can continually repair its nucleic information. These guys actually hang out in nuclear reactors... not exactly where you'd expect to find life, is it?

In terms of actual mol. bio. makeup of extraterrestrial life, we're not sure. In fact, we don't know what the abiogenetic source of life is on this planet. Right now RNA seems to be a popular molecule for looking at evolution and there are those that believe the first life used RNA both for its folding and activation abilities and its information storage capacity. Whether this can be proven or not remains to be seen. What I'm getting at is that we don't know how life ended up the way it is here so it's probably not going to be easy to guess about it in other places.

Is there exotic life out there? Well, almost certainly if you ask me. There's just so many options when the universe is as big as it is.

I can give you another guess: if we find evidence for life on Mars or Europa it's most likely going to be of a similar to that of Earth's if for no other reason than the conditions we expect to find the life in (where we will look) are going to be conducive to conditions that we know life exists on Earth.

Colt
2003-Feb-08, 08:35 AM
I remember that when one of the Apollo's landed on the moon one of their objectives was to check how an earlier probe was standing up to the radiation. They found life on it. Bacteria from Earth that was still alive. /phpBB/images/smiles/icon_biggrin.gif Not sure if that is exactly how it goes but sounds about right. Also, they sent up a type of bacteria in a satellite and it was exposed to hard-vacuum and radiation and was fine when they brought it back. Anyway, night. -Colt