Imagine there was another Earthlike planet in our system

[dark2112]

Well, let us remember a few things when making that comparison:

1) The Niña had a complement of 24. The two missions to Mars being talked about much these days have crews of 2 and 4. For social animals like humans, this is a major difference. And while Columbus' ships were small, they still had notably more room than a Dragon capsule - you could walk around on deck, if nothing else.

2) A 3 month trip on a small boat isn't fun. The Mars missions under discussion are more like 8 months one-way.

This is not to say it is impossible, but merely to be realistic about what we are asking.

There are logistical challenges, yes, but the general attitude is that they are insurmountable, which they are not. We assume that our technology is at the same level today, which may or may not be true with 60+ years of confirmed knowledge of extraterrestrial beings in our solar system, but even with no additional impetus to develop space technology any further than what is available today, we do have the technology to build a space ship capable of carrying 24 people. It's a matter of cost on why we don't, and I suspect that with a known alien species at the other end, we could come up with that funding over say, a 20 year development plan that could have begun in the 70's. I also suspect we would have built some semi-permanent moon base by now, allowing the larger ship to travel from our moon to one of Mars' moons, cutting the cost of running such a vessel considerably, since we'd only need to boost our ship into space once. A large part of the cost of any mission is the expense of lifting all the weight out of a planet's gravity well, but if that is defrayed over a larger number of missions, it does become economically feasible to trade luxury items and items of high scientific value. Martian spiders that can spin their silk in thicker strands at a higher tensile strength could potentially replace steel alloys in suspension bridge construction, for example, making a land bridge across the bering strait much more economical.

Even if we scaled it down to say, a ship designed for 6 or 8 people, you also don't account for the difference near-instantaneous communications would have for socialization purposes. Looking at similar areas of isolation, Antarctica has 70 research stations and a population of 1000-4000 people, depending on season. In the winter, assuming even distribution of the population among those stations, you're looking at an average of 14 people per station. Additionally, Sergei Krikalev managed to live 10 months aboard Mir during the dissolution of the Soviet Union, and that had a maximum crew of 3 people.

There is indeed a psychological component to the extreme isolation such a journey would entail, but we already have people who've been in similar situations in the past, and it isn't hard to arrange a dry-run of potential candidates to see how they'd react to living and working in small confines with the same crew of people. The reason this is even considered a barrier at present is because a manned mission currently can't bring home anything that a robotic probe couldn't do safer and cheaper. Having an entire world at the other end changes that entirely. Even if the lifeforms on our psuedo-Mars were completely different than anything on Earth, it would still give us another view of how life could have started, a different set of data to add to what we know of evolution, etc.


Edit: Replying to the post by Morrus, you are correct. Further research has proven my ignorance, the flat earth theory was largely abandoned around the turn of the millennium, even among the uneducated populace. I withdraw my incorrect assumption.

 

[Dannyalcatraz]

And unfortunately, The Flat Earth is an idea that refuses to die.

In that, it perfectly presages that aspect of Internet culture in which, even though the facts of a matter maybe quickly and easily found & verified, no misinformation has failed to find an audience of believers.

 

[Morrus]

There are logistical challenges, yes, but the general attitude is that they are insurmountable, which they are no.

Nobody thinks that. Nobody in this thread, and nobody I've ever encountered. It's utterly possible, and everybody knows it.

The common objection is that it's expensive; which it is. As indicated earlier in the thread, Mars One is costed at $6bn, all in. Expensive, but George Lucas could personally fund it. But that's a rewind of the thread by a couple of weeks, so let's not dwell on that.

 

[Dannyalcatraz]

A Mars mission funded by George Lucas would be doomed: he'd want to include at least one annoying astronaut, and that would lead to at least on if not multiple deaths.

If Ted Turner did it, OTOH, at least one of the female astronauts would be hot, so he'd partially recoup his expenditures with merchandising.

And Hugh Hefner would...well, lets not dwell on that.

 

[Derren]

That's a myth invented by popular fiction. The flat earth was never a popular opinion. Even uneducated medieval folk could see that was ludicrus; there's no shred of evidence to suggest that such a thing was a widespread opinon at any time.

And for that there is of course evidence, right?

And be useless. They're all short-range. We don't have the capability to blanket the entire solar system from, say, Jupiter inwards with active radar. The power requirements alone would be absurd.



Pretty much everything that the sun shines on emits heat. If it is using something a bit more passive, like a solar sail, it may appear just like a large rock in IR.

Nations have no problems plopping down a few nuclear power plants when it comes to the military. Besides, we just need to monitor mars and track any outgoing vessels. Not cover the whole solar system.
And thats why IR is so great. Everything which emits heat, either through self generation like rockets or just by reflection is clearly visible against space either because there is no heat radiation behind it so it stick out or because there is so much heat radiation behind it that its a black spot (when viewed against the sun).

 

[GSHamster]

And for that there is of course evidence, right?

http://en.wikipedia.org/wiki/Myth_of_the_Flat_Earth

That seems reasonably thorough.

 

[Morrus]

And for that there is of course evidence, right?

Yes. Tons of evidence. Reams of documentation from the time. An overwhelming quantity of it which makes that fact as established as gravity. I won't insult you by linking to the "let me google that for you" page, but there's the entire scientific and historical community in 100% agreement on this one based on vast amounts of documentation. Nobody has believed in a flat earth in many, many hundreds of years.

The only odd part is that you're even asking the question! I assumed it was common knowledge. I guess not! It would appear that there are more people today who think Middle Ages folk believed in a flat earth than there were actual Middle Ages folk who held that belief. That's mildly embarrassing.

 

[Dannyalcatraz]

Nobody has believed in a flat earth in many, many hundreds of years.

...except The Flat Earth Society. (NOT a big group.)

 

[dark2112]

It would appear that there are more people today who think Middle Ages folk believed in a flat earth than there were actual Middle Ages folk who held that belief. That's mildly embarrassing.

I blame hollywood and my lack of interest in digging further to find real evidence for my own ignorance, and yes it is embarrassing.

Not wanting to dwell on the expense of these missions, if the common objection to any of the various scenarios is the primary difficulty, and we've established that the cost can be paid if there is a reason to do so, all we have to provide is evidence that there would be a significant portion of people in positions to pay those costs in order to actually go ahead with the missions that have been proposed.

I personally think there would be a lot more interest in establishing trade than war, but that depends a lot on our assumptions. A trade relationship assumes that whatever life we find over there is at least compatible enough that we can communicate with them, because without communication, there can be no trade. An alien race that we can't establish any sort of common ground with, such as perhaps a telepathic hive mind race that doesn't view us as intelligent, would lead to war. Once it's established that there's a race that will eventually expand outside of it's own boundaries and take our planet from us, we'd definitely have the provocation to spend the money for war purposes. The other side of the coin, is that we would probably have a privately funded expedition in place to send an explorer on a cultural and/or trade mission, and the likely result of that would be some sort of interplanetary trade. I find it hard to believe that an entire planet would have absolutely nothing to interest us enough to justify the return trip cost, especially since we'd almost certainly make the initial trip.

So really, unless my assumption that cost is the primary difficulty is wrong, this discussion essentially boils down to whether or not this alien culture is similar to ours, or completely unable to be understood. If similar, some sort of trade is the likely end result, due to the evidence of humanity's various explorations across the globe and the expensive trade empires it's already created. If not, some sort of containment action/war is the likely result, and the only real question is if we have the means to enforce that with today's technology.

If we're assuming eventual hostilities, and assuming that radiation has a similar effect on their environment as it does on ours, how feasible would it be to transport largeish amounts of radioactive materials (radioactive waste as the primary source, moving on from there if needed) near their planet, if the goal were simply to seed the atmosphere with radioactive materials? How much radioactive materials would we need to seed an earth type planet with enough radiation to begin killing off or sterilizing the larger lifeforms?

I do like the previously mentioned idea of an ion drive ship sending asteroids into mars, for the purposes of war, but aiming interstellar objects is pretty tricky, and I'd see that as the bigger challenge to that idea than anything else. They would eventually see it coming, and I'm sure we could attempt to delay any efforts to halt it with modified conventional weaponry platforms (projectile weaponry fired upon any martian ships that come near the asteroid, for example), but with the timescale of such an attack (years, likely), the bad luck of an early detection or poor aim could very well send these asteroids closer to our orbit, and would make it easier for them to use our own failed projectiles in a similar attack against us.

 

[Derren]

If we're assuming eventual hostilities, and assuming that radiation has a similar effect on their environment as it does on ours, how feasible would it be to transport largeish amounts of radioactive materials (radioactive waste as the primary source, moving on from there if needed) near their planet, if the goal were simply to seed the atmosphere with radioactive materials? How much radioactive materials would we need to seed an earth type planet with enough radiation to begin killing off or sterilizing the larger lifeforms?

My guess is a lot with no guarantee of success (even when they are not intercepted) and it will certainly not be quick. Radiation damage is pretty random unless you get a massive doses which is basically a nuclear warhead. Counting on the explosive effect is imo a better idea than on long term radiation ones.
Don't forget, there have been 2.500+ nuclear tests on earth so far + 2 (and a half) power plant meltdowns with hardly any effect on the global population.