Does Life Exist

[geoschmo]

Originally posted by JurijD:
We have the technology to construct self sustainable environments... there are about 200 of them floating uder the worlds oceans (called nuclear submarines) They surface once every 6 months only to resupply on food beause it would be too unpractical to have it produced on-board. Everything else... water, oxygen, heat etc. is produced by the nuclear reactors that turn CO2 to O2 and recycle urine and the vapour in the air to usable water....

No, you are missing my point. I wasn't talking about renewable recourse like food and water. I know we are very close to or have acchieved teh basic technology needed for these things. I am not even talking about basic energy needs. Nuclear power is a good long term option, and there is some talk about magnetic scoops to pull hydrogen molecules from the surounding space.

I am talking about the huge amount of raw materials and manufacturing capability you would need to be able to build replacment parts for all the myriad pieces of technology on board the ship. It's not simply a matter of scale, or making a larger ship. Because the bigger you build it and the more equipment you have dedicated to these support functions, the more things you have that can break. It's a curve that I am not confident you can ever get ahead of when you consider you are looking at decades long trips at least.

The submarines are not nearly as self-sufficent as you think. 6 months suberged is nothing. They can surface any time they need and head for a repair dock if something breaks. Or a helicopter can bring them a new circuit board in a matter of hours.

[geoschmo]

Originally posted by Ruatha:
I think you are pretty alone in thinking that it's technology that hinders a manned mission to Mars.
Today it's mostly economics, the cost will be huge.

Actually if you read the recent literature most of the scientific community now believes that Mars colonization is out of our current technological reach. It is NOT simply a matter of money. Recent findings are that the radiation levels there are much higher then we previously believed among other things.

I think most agree that eventually we could have colonies on Mars. The question is whether we are capable of having self-sufficent colonies on mars. And I mean TOTALLY self sufficent. Not dependant on regular replenishment shipments from Earth with spare parts, etc.

Only when we can do that can we even think about sending a ship to another star. And that will be more difficult because at least on mars you have access to the planets raw materials.

A good example of what I am talking about is the Int'l Space Station. It is not anywhere near self sufficent. One accident grounds the Shuttle fleet and you hear talk of abandoning it alltogether. Even keeping it operational is tough. Depending on teh Soyuz means only two crew members can remain on the station. And those two are so busy doing station maintenance that they complain they don't have time for research. More money would not make it self sufficent. It might give us better options for replenishment, but wouldn't make the station self suficent.

[ August 08, 2003, 15:33: Message edited by: geoschmo ]

[kalthalior]

Did the Drake equation thing that Slick posted, used pretty pessimistic figures (by my standards, anyway) and arrived at N=3. Interesting. Additionally, went out and found this:
Mars Colonization Plan

Might be a little on the optimistic side, but it does spell out a fairly serious program. Also, I will admit to be a tad biased in favor of Mars colonization -- I'm a member of the Mars Society.

Mars Society webpage

[Ruatha]

I gotta read the Posts better before I reply, sorry.
I missed the first post and replyed to the reply, thought it was about a simple two-way mission to mars, Colonies is something enterely different, I agree on that!

My sincere apologies, it won't happen again, ever, promise

[geoschmo]

Originally posted by kalthalior:
Might be a little on the optimistic side, but it does spell out a fairly serious program. Also, I will admit to be a tad biased in favor of Mars colonization -- I'm a member of the Mars Society.
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I totally believe Mars will be colonizable someday. I was merely commenting that we aren't there yet. And not just fomr a lack of money or political will. There are definite, significant technological hurdles that need to be overcome for a permanant habitation. Self-sufficency is a long way past that, although I believe both are possible.

I just question whether it will ever be possible to build a ship that can travel between the stars without all the crew dieing and the ship turning into scrap metal before it gets there.

I do however believe life exsists out there. I think someday we may figure out a method of communication with them and be able to learn about each other. I am just not confident we will ever be able to visit them.

I can envision a "galactic internet" with information being shared about the various worlds and races. We could use this information to design virtual trips to these places.

[JurijD]

[quote]Originally posted by Suicide Junkie:

No, because when you send out a signal pulse, it moves out in a spherical shell. The area of the shell is proportional to r^2. Dividing the signal out along that surface, you get 1/r^2

yes, yes I realize that normal enery disperses at that rate because of spacial enlargement... but Em waves are a combination of magnetic and dipole movement... I haev a vague memory that my physics book even has it derived somewhere that EM transmissions actually fade at 1/r^3 because of dipole movement on the antena...

I fo course could be wrong .. it´s been two years since I studied physics carefully

[ August 08, 2003, 16:13: Message edited by: JurijD ]

[Slick]

Originally posted by kalthalior:
Did the Drake equation thing that Slick posted, used pretty pessimistic figures (by my standards, anyway) and arrived at N=3. Interesting.

Also, note that the Drake equation was formulated to look for life that can communicate with us. As such its numbers are for our galaxy alone because the assumption is that other galaxies are too far away to pick up individual signals.

So if the question is about "intelligent live in the universe", Drake equation would have to be multiplied by the "biyyllllons and biyyllllons" of other galaxies, and the term about communication dropped.

Slick.