-- NASA Dawn Mission Status: Spacecraft Tests Ion Engine
http://www.spaceref.com/news/viewpr.nl.html?pid=23755

"NASA's Dawn spacecraft successfully completed the first test of its
ion propulsion system over
the weekend. The system is vital to the success of Dawn's 8-year, 1.6
billion-kilometer (3-
billion-mile) journey to asteroid Vesta and dwarf planet Ceres."

Thats ok, you did not do anything wrong, it is only bad form if you continue doing somthing in somones thread after they ask you not to. Of course You don't know what they want before they ask it!

phew, here goes guys.

here's the short version: argue not concerning God. i'm not saying "don't use the G-word," i'm saying not to attack others' beliefs directly.

the long version.

some of this may be re-cap, but i'm re-capping for Mystikmind since he wasn't here for earlier episodes. i'll write about people other than myself in the third person, to remain clear.

i guess i'll start by saying that i loathe censorship. it's come up before that other participants don't wish to see this discussion degenerate into "another religious thread", and i agree. it's not that i don't enjoy a good discussion about religion, it's just that i think it's almost impossible to have a good discussion about religion. people are too personally invested, and any productive discussion that moves into new sub-topics tends to turn into circular arguments amounting to "you're wrong and i'm right," and "well i'm rubber and you're glue."

my biggest goal is to keep this discussion vibrant and productive (by 'productive' i mean that people continue to inject new ideas and learn, even if it can't be avoided that some old ideas are re-hashed and such). i don't think anyone has to avoid religion entirely to remain respectful, but it's tricky.

so here's an example. in reply #508, Mystickmind started, "Well if you believe the bible as i do..." Here, "if" and "as i do" show a great deal of respect for other beliefs; they serve to make the statement relative and reflexive. i think it's a good thing in this case that he brought up his belief in the bible: it helped make his subsequent statements and ponderings more clear. i believe he implied a request from others for more knowledge that he didn't have, to correct his own misunderstandings and ultimately to give him even more to ponder about.

in #518, when danielost said "and according to someone it was all an accident", it was dismissive to those "someones". that may have not been his intention, but when you don't take more care about the words you use his intentions and points can be lost (especially on the internet, when the 90% of communication which is non-literal is mostly lost and only at best emulated).

it's not as simple as god/no god. a while back, someone else left a quip, was in Vinraith?, about why something so obviously meant there was no god. and i asked him not to make comments like that.

i ask no one to hide their own beliefs, or anything about themselves for that matter (except perhaps unsightly growths), and i feel sad when they do. i do ask everyone to respect each other, beliefs and all. i know what it's like to believe, in every sense of the word, in your heart of hearts, that your belief is right. what i'm asking participants then is to accept that their belief is one among many, regardless of whether it's the right belief or not, and to show other people, at least here in this forum i started, basic respect -- i'm not even aiming for fraternal love or anything so high-minded. i think that's manageable and reasonable (and i might add, productive to learning of all kinds), and i think anyone capable enough to use the internet is capable enough to discern and use the basic signs and signals of mutual respect. speaking from personal experience, it takes only a little bit of energy, and it brings great returns.

there are no ultimatums to my requests; they are merely requests made magnanimously. with anything short of spamming or utterly offesnive profanity, i frankly lack the energy and drive to say 'told you so' to use any means but words. words are cheap.

and danielost, i'm sorry if you feel picked on. had anyone replied to Mystickmind's "if you believe in the Bible as i do" with something insulting to his beliefs, i would have just as quickly asked that person to leave that kind of talk elsewhere. i hope this difference is clear enough to understand. if you'd have just said something more like "and that's one of the reasons i believe in the bible" to the talk about genetics, it would have been totally fine, harmless, and not in the least bit "hiding who you are." but instead you commented in a dismissive way about others' beliefs - if you're really the type of person who looks down on others so harshly for different beliefs, and if nothing else can't keep it under control in here -- well, i don't believe that's true in the first place, so i won't end that sentence.

Agree 100%!

Yes most of us do dislike sensorship but also i do understand people should be entitled to direct their own threads to some degree.

Also i understand that a high level of respect in a persons speach is quite a complex quality that needs to be learnt, and is usually learnt the hard way over many years through trial and error. This forum is a fantastic place for such lessons to be learnt!

all i was saying is that dna is too complex to be an accident. i am sorry but i had to point that out.

you know, you're absolutely correct. i guess i take it a little for granted. i live in a densely populated and diverse city, and i'm used to speaking with people who likely have very different beliefs, experiences and outlooks than i do. one thing i think, though: it's better to say more, and especially when you can re-read it before posting, decide what can be left out, than it is to say too little, post it, and only realize after that fact what you should have put in.

---

in my last post, i should have also put in: the only reason i jump on things i think could be disrespectful so quickly is because they can snowball quickly, and i fear if it got too far too quickly there wouldn't be much anyone could do to save the great discussion we've got going.

even that's a little far, when with seven extra keystrokes you could say "i think dna is too complex to be an accident" or for 9 you could get the extra umph of "i believe".

but as it is, you state it as a fact, and it's a fact you can't prove. that's the kind of insensitivity or carelessness that can spark bad arguments.

did any of you check out the two web pages i posted. yes i know you had to work to get to them. one was on ion engines. the other was a space elevators.

Well i would agree that evolution does not justify how DNA came to exist, Thats why they still call evolution a 'theory'. But weather you believe in God or not, i'm sure everyone would agree that how DNA came to exist is indeed a mystery worth exploring!

here i'll make it easier:
NASA's Dawn Mission
Competition for a Space Elavator design

i could definately see those ion engines being a major part of near future exploration in the solar system.

I was thinking, we have talked about colonizing an Earth-like planet, but what about very unEarth-like planets? Would we have a reason to go there that would make it worth colonizing? How would we do it?

I bring this up, not just because we seem to have digressed a bit and I want to get back on track, but I was inspired by a recent article I read about Titan. Titan, one of Saturn's moons, is a seemingly inhospitable chunk of frozen waste, but let me describe it to show you what I'm getting at. Being so far away from the Sun, and with no noticeable geothermal core (not that we really have the capacity to tell that at this point), it is really, really, cold; roughly -200 degrees Celsius. The most of the planet is composed of a variety of light compounds such as water, ammonia, and some light hydrocarbons such as methane and methanol. The frozen water of the outer crust is as hard as rock; in fact it behaves much like stone does on Earth. The atmosphere is composed of nitrogen and methane, but this atmosphere is thick enough to pressurize some of that methane, condensing it into lakes and oceans. Doesn't sound much like Earth, does it? However, satellites have picked up evidence that, despite the difference in predominant chemical composition and drastically lowered temperatures, in combination these features behave very, very similarly to Earth. It rains (methane, of course), it has seasons, the icy ground functions pretty much the same as rock as I said earlier. There are mountains and cryovolcanoes, which spew up the cryomagma of the mantle, which is liquid water and ammonia. There are "sand dunes" made of grains of ice crystals, wind patterns and rivers of methane shape the icerock into very Earth-like formations. Basically to sum it up, picture Earth, where any instance of dirt or rock is replaced by water, and any instance of water on Earth (oceans, clouds, rain, etc) is replaced with methane. Oh, and did I mention it's cold?

But anyways, I thought that this was definitely qualified as the sort of kick-butt imagery that dystopic mentioned in his inaugural post, and would make an interesting setting for any book dystopic writes (yes, I know you're already pretty much set for your first plot. Emphasis on the 'first'. ). Now, what I'm leading you to, is my topic: discuss the possibility/methods of harnessing the resources of any world, not just Earth-like worlds, to create a viable colony. Most colonization theories involve terraforming, trying to convert radically different systems to new Earths, but I think that this may be the wrong tack; we need to develop processes to utilize the existing conditions of a planet/moon, Titan being my example. While Titan seems like an uninhabitable world, this place is probably the most habitable world in our solar system (aside from Earth). Think about it, it has an abundance of A/ water, a necessity for any life, and B/ methane (a.k.a. natural gas). More so than lunar, or even martian bases, Titan has the best conditions for a self-sustaining colony. The methane provides enough energy to last....a heck of a long time. Water is by no means scarce, and we could use electrolysis it to get plenty of oxygen. I don't know too much about the specifics of agriculture, but I know that nitrogen fixing is an important part of all plants, and definitely one of the limiting factors to any extraterrestrial agriculture is a lack of available nitrogen compounds. Titan has huge quantities of ammonia, pre-fixed nitrogen. Despite the obvious complication of distance from Earth, which makes the moon more likely a candidate for colonization, your setting is in the interstellar 'phase' of space travel. We may simply not find another Earth anywhere in reach, so knowing how to colonize a Titan-like world would be important.

Just remember to bring a blanket.

Such a moon would probably make an excellent mining colony. Mining recources for space stations situated in a more favourable solar orbit! or for spaceships. Its low gravity would make that process much easier than taking recources into space from Earth.

and the further up a grav well you are the easier it is to drop cargo. ie use gravity to propel your cargo instead of engines.

i'll reply more on milltertime's post later, but for now i thought i'd point out that we passed "Show off your ship designs 2007"!

  

Hmmm i have some very nice ships i could post! I made a series of ships that look like various insects, and they are extremely fun to use in the game!

don't know if any of you have read this yet. but titan does indeed have lakes and seas. but unlike on earth where they fill up during the spring and summer. titans lake fill up during winter.



WWW Link

you may run into a problem mixing natural gas and oxygen.

I like the titan Idea. Well let's see if we can figure out, what at minimum, we need for a self sustaining colony:

Energy - As is a usable power source, whether it be solar, or we bring it with us.
I'd assume, since its so cold, that Solar wouldn't produce much power. We'd probably have to brin our own power source. Using electrolysis to produce O2 and burning the methane would work, Barley:

4H2O +CH4 -> 4H2 + 2O2 + CH4 --> CO2 + 2H2O + 4H2
P - R
0-4(-241.83) = 967.32kJ/mol used phase 1
(2(-241.83)+(-393.509))-(-74.87) = -802.299kJ/mol generated phase 2

Hence we'd get 165.021kJ/mol for every run of our reactor. Not to mention that some of this energy would be lost through the efficiency of the generator and electrolysis devices. Its really not a lot of energy besides we'd have huge amounts of Hydrogen and CO2 as by products. To put in perhaps in more undertstandable terms, that's about 40 Calories (1/3 of my can of soda) for 72 grams of water and 16 grams of Methane (1 pound is 453 grams) Someone check my math - I prolly made a stupid mistake, lol

But there's a big drawback - All the oxygen is consumed in this reaction. It we wanted to make extra oxygen to say, breathe, it would cost antoher 241.83kJ/mol. Meaning we'd be using more energy than we are making...

What about nuclear? does Titan have nuclear materials that we can get at? Or perhaps Using a Reacctor Fueled by earth as an additional power supply. We wouldn't need constant shipments of fuel and it would be a good power source

Food - Well we have water - that's great. We'd have to kick start our own agriculture and light it ourselves, not to mention heating it. Nice thing about methane is that its pretty basic and can be converted to other organic compounds fairly easily. The CO2 from the generators could feed plants - that would be edible.

Structures - Snafu #2, I beleive. Does Titan have metals? If not everything would have to be sent from Earth to build structures. That's not a terrible thing. But, These structure would have to be fully enclosed and capable of withstanding the very cold temperatures of Titan. Not to mention that these structures would pracitcally have to be "Heat tight" as if they started to warm up the ground (ice remember?) our colony would sink into the planet - that would be bad. There would also be a wieght/area limit as concentrated pressure will convert ice to water.

I know we have a scientific base in Antartica - But I get the feeling that the temperature inside the base is not very warm (barely above freezing) and its a very small base compared to the size of our colony. Perhaps building the base so teh foundation sits on struts drilled deep into the ice?. The bottom of the struts would then have perpendicular sub structs extenting horizontally releiving the pressure on the ice. That way if the colony does heat up the ice imeediately below it, It would still be resting on the structs well below the thermal zone. We do somethign similar on Earth for building on marshy ground (The foundation sits on concrete pillars drilled all the way to the bedrock to keep it from sinking)


I think the biggest hurdles would be building on the ice, the cold temperatures, and an energy source. I'm not saying its impossible. I think a nuclear source is the best to go. Struting the colony would be hard to do, but possible. And we'd just need very insulated buildings with as little surface area as possible (Ie simple shapes)

Don't forget the low gravity, so footings would not need to be nearly as extensive as they are on Earth.

very true, I did forget about that. So, correct me if I'm wrong, but that would make It Easier to build using the strut/footings as we'de need fewer and they wouldn't have to be as extensive?

I guess the other hard part would be insulating the structure. I mean we would want amibent temp to be around 68-72 and possibly warmer if we are growing food, etc. I think heating up our colony would be pretty expensive in terms of energy and we wouldn't want to lose any of that to the atmosphere. Do we have insulations that can do that in large scale?

the only thing i can think of that can do this are polar bears.

I dunno? i asume your not talking in degrees celcious?? What is that stupid temp scale you Americans use... farenhight or somthing? And you guys also use pounds instead of kilos. So whenever i am watching some American show on TV, and they mention the temperature or the weight of somthing, i dunno what there talking about!

NB; i soon gave up watching the American version of the biggest looser! who is loosing what weight? i dunno? i have no idea? why am i watching this show?? lol

according to st. voyager. we are supposed to have had a colony on mars for 4 years now. and we could have done it.

Hm, hadn't thought about that. Are there any other ways to extract energy from methane; possibly a chemical reactor using the ammonia or any other abundant chemicals on titan?



We aren't able to determine anything from our current data. The leading theory states that there must be an inert core of rock inside Titan, surrounded by a liquid water/ammonia mantle. We already have experience with submarines; we could probably make some sort of craft to go down to the core and mine it, but there's no telling if we find anything useful.

Speaking of water mantles, since the mantle is liquid water, it must be somewhat warmer than the surface (though ammonia would lower the freezing point, but I don't know how much). Perhaps it would be easier to make an underwater colony: we wouldn't need to worry nearly as much about insulation against heat loss, and we'd be right on the core, so we could mine directly on the core instead of having craft go back and forth between the surface. Only problem is now we are more distanced from the methane, but since it would be above us I assume we would have to do no more than build a pipe and the methane would flow downwards due to gravity. All in all, underwater may be the way to go. Rapture, anyone?



It's Fahrenheit. And while I agree that the metric system is simpler in most respects, the Fahrenheit temperature scale is more useful to the average citizen because smaller denominations translates to higher accuracy.

in general chemical energy sources are inefficient, at least when compared to nuclear sources. at least the way we build them. with the exception of the renewable energy forms, most of our energy sources are all steam generators, the big difference being how heat is created. methane does have lots of hydrogen we could use for fusion, and the carbon could be a useful building material (carbon filaments).