Diche Bach

Details? What are the rewards for the principals and backers? What are the inevitable rewards to humanity: meaning, the rewards even if the short-cut methods followed contribute to catastophic failure, 100% fatalities bankruptcies, suicides, and tragedy on the news for months on end? Failure is not an option, at least not if the point is to PROMOTE this Multiplanetary species thing. The first three missions must be utterly successful or the whole zeitgeist might be set back decades.

Look, I'm not saying that colonizing Mars is impossible. It is clearly POSSIBLE. I'm saying: there is a smart way to promote that eventuality and a stupid way. Taking shortcuts is the stupid way. I don't see the value added by taking short cuts to get people to Mars which increase risk and do not provide long-term sustainable solutions.

I would say there is another reason people have not colonized Antarctica: The Return on Investment does not exceed the risk to reward ratio (by which I mean all the "risks" including the sheer discomfort and long-term life history impacts, even if you don't die).

Ahh, 80 days to Mars for ~10 km/s . . . how big of tanks is that? How much dV did they use in the Apollo missions?

I managed to get it to show me a trajectory with a transit of 350 days. You telling me I should tell it a one-way trip?

Very cool tool. . . https://trajbrowser.arc.nasa.gov/traj_browser.php?NEAs=on&NECs=on&chk_maxMag=on&maxMag=25&chk_maxOCC=on&maxOCC=4&chk_target_list=on&target_list=Mars&mission_class=roundtrip&mission_type=rendezvous&LD1=2017&LD2=2040&maxDT=120&DTunit=days&maxDV=20&min=DV&wdw_width=365&submit=Search 20 km/s 2017 to 2040, 120 days (re the "4 months" Dal referred to) : Query took 1.49s, returned 0 trajectories. Try relaxing constraints on ΔV or duration and opening the launch window. Right, so why haven't people colonized Antarctica? There are even MORE resources there, plus penguins, air, and inherent radiation shielding (in the sky)?

4 months how? Citations please. Re: the "costs" of space travel, Who are Elon's consumers? Am I or you benefiting directly from these cost improvements? If not, then whom? "ITS" never heard of her.

Why climb Mt Everest when you can send a robot drone there? For a fraction of the cost and virtually zero risk of human harm. And BTW, personal journeys like climbing a mountain because they find the experience enriching should not be portrayed as analogs of national or at least collective social projects to advance the human condition. There is no reason to go to space except to advance the human condition. Climbing Mt. Everest does not appreciably advance the human condition, and neither does sending people into space on shoe-string budgets using iffy designs whose ethicality will almost certainly be brought into question in due course.

To be completely honest . . . I am deeply offended at even the mere suggestion of "sending humans on a journey to Mars" much less "colonizing Mars" when "we" the human species have yet to: 1. Build a functioning space habitation in orbit. By which I mean, one which affords its residents at least some semblance of artificial gravity as they go about their daily lives. 2. Build a somewhat self-sufficient outpost in orbit. By which I mean, a space station with sufficient solar power and arcological integrity that it can function (meaning sustain human life and its day-to-day functioning) for up to 2 years without any need for resupply from Earth. 3. Build an orbital ship construction facility and fuel depot 4. Fetch an appropriate asteroid that can provide a strategic range of raw materials for future projects at the orbital shipyard 5. Build a space craft at the orbital shipyard that derives at least 50% of its materials, fuel and propellant from off-Earth sources. At that point, discussion of 7. Sending people back to the Moon, and to Mars will be prudent. Once at least 5 manned missions to Mars have been deemed an overall success, then discussion of 8. "Preliminary Steps Toward Long-term Habitats on Mars" will become prudent. 9. "Colonizing" Mars? Why? Why on Earth would we imagine it to be meritorious to project a future in which children are born in a hell hole like a rough underground concrete bunker on Mars? Oh yes, the "multi-planet species" thing, i.e., save us from extinction of Earth goes birds up . . . Okay fine. Long-term not a bad ethos and even reasonable and salutary, though there are lots of ethical questions about people giving birth to the first children off Earth which even the most broad-thinking authors of science fiction have yet to really address, much less entrepreneur web-site salesmen like Elon . . . However, putting the Colonization cart (see Step "9" above) before the horse comprising steps 1 through 5 (*See Note below . . .) is such utter fatuity it defies comprehension how otherwise intelligent adults can fall for the sales pitch. If all you manage to do is "get people to Mars" and maybe "get them home" then you STILL have to do steps 1 through 5 in order to have any prospect of a sustainable long-term "colonization" production and supply chain. (*) Note: It is possible human beings could survive a 2 to 3 year journey in micro-gravity. But at this point we really don't know. More importantly, we really don't know what the long-term effects would be on their health. Given that the mechanics of generating centrifugal forces that can simulate gravity are not tremendously challenging, I consider manned-spacecraft which skip the "generate gravity" stage of things to be inherently unethical and believe that, in a very short number of years, such spacecraft will be made illegal for use as long-distance vehicles because of their health impact. Likewise, the mass of carrying along 2 to 3 years of provisions is probably not so much as to dramatically impact the engineering of the Mars craft; in sum, you don't HAVE TO HAVE a self-contained, self-sufficient arcology onboard the first Mars craft, i.e., one that recycles the atmospheric, nutritive and liquid wastes and resources and requires only infrequent "top ups" with expendables from Earth. But when the first Mars mission suffers a catastrophe and there are three or four survivors in the wreckage on Mars, who now face 2 to 3 years before they can be rescued and have only some 6 months of provisions left, and virtually no facilitate to setup a long-term habitation with replenish-able food, air and water, then the Elons of the world will be shown for what they are: con men else delusional.

Elon would be okay with dying on Mars. He didn't say ANYTHING about dying in a tiny spinny thing in orbit . . .

Interesting. I have as much difficulty comprehending this as I do comprehending the apparent finding that: the interstellar medium (which is NEARLY an empty vacuum? right? I am right on that point . . . right?) is also extremely "hot" ?? (Eh, what!? How can a nearly empty medium with almost no atoms to bang around in it be "hot?") . . . Based on reading cosmologist descriptions of the evolution of the early universe, where "epochs" can range in temporal duration from a few nanoseconds to billions of years, and where at various points, "matter" was nothing" and nothing was "everything" and "elements didn't exist," etc., I have a strong suspicion there WAS an epoch somewhere along the line where the interstellar medium DID in fact reflect the "chocolate pudding" consistency which is depicted in the spacecraft physics in EVE Online. Small solace for a massive confusion I say.

Well, the issue with Proxima b seems to be that the high rate of rads bathing the rock would have ionized the molecules that would have been its nascent atmosphere thus "stripping" it of its atmosphere over time. ADDIT: and that is, I presume based on an assumed magnetosphere for Proxima b that falls within the "expected range" for a rock of its size and suspect composition. So my question(s) is(are): 1. How big/powerful does a magnetosphere have to be to prevent that level or solar atmosphere killing 2. Is it even possible for a magnetosphere to do that? 3. Are there other ways that an atmosphere could have "survived" within a close enough range to Proxima that they are "warm enough" for liquid water (thus the interest in moons of frozen giants).

Hey Green Baron! Good to read you yet again! So what you're saying is actually music to the ears of a fiction creator! "Could be . . . ," being the central message!

Simple life (as in "not-complex life forms"): almost assuredly exists outside Earth and possibly even within the Sol system. Indeed, it is probably "abundant" from a cosmic standpoint; meaning for the 1,000,000,000,000,000,000,000,000 (one septillion else "quadrillion" depending on which country you are in) solar systems estimated to exist in the known universe (that is 1 x 10^23 for you scientific notation lovers out there). It seems safe to assume that the chances of life emerging at some point during the last 15 billion years in the old Universe at large is at least no "worse" than a one in a septillion chance (1 in quadrillion if that is your thing) based on the fact there (a) is life on Earth, and (b) there are probably (maybe) around a septillion solar systems in the universe. However, when we stop and consider all the ROCKS (and not just all the star systems), chances go down. Just for the rocks in the Sol system, we can say that the rate is--at this point apparently--at least no higher than 1 in a million (-ish), though with the Oort Cloud and Kuiper Belt that might ratio might plummet substantially(?). We might assume comparable numbers of celestial objects to Sol system (~10 planets, ~1,000,000 minor planets and other sundry rocks: That works out to be Total "rocks" that might support "life" 1,000,010,000,000,000,000,000,000,000,000 one percent of the above number 10,000,100,000,000,000,000,000,000,000 I don't think there are words for such numbers? Ah hold on . . . WRONG! Names of large numbers That is a LOT of rocks. I wouldn't be surprised if >1% of all those celestial objects had icings of blue-green algae-like actively cooperating membrane-bound replicase molecules that could meet all the standards for defining "life." clinging to the sunny spots on their surfaces . . . Such simple life, even if abundant is however, likely only of academic interest at the outset, though of potentially vast interest to biological sciences in the long run (and enormous importance to humanity). "Complex Life:" (meaning probably eukaryote-like degrees of cell complexity). I think is far more speculative question. The emergence of this complexity of life on Earth seems to have taken a very long time to occur (something like 2 billion years after the formation of the planet, which is at this point still nearly half of the total age of the Earth) and been facilitated by a series of cosmic historical accidents which may be quite rare even in the entirety of the vast Milky Way. Life that will be of interest or value to humans within the next 10,000 years? unlikely but well worth all efforts to discover. By this I mean: small puddles of goo living in caves on Mars, or perhaps even more complex squiggles (MAYBE! even eukaryote-like squigglies!) living in the oceans under the surface ice on one of the outer planet moons. Again, like I said, any life discovered within the next 100 to 10,000 years is likely to be of initially only academic interest. But once a few years of thorough analysis have taken place, the revelations about evolution and biology which such life might afford could well revolution biology, medicine, psychology, and many other fields. 1. Life: absolutely! 2. Complex life: possibly but Earth might in fact be THE ONLY site in the entire vast cosmos 3. Garden Planet Ecological Scale "Life:" extremely speculative. Rare Earth Hypothesis suggests that garden planets like Earth might be exceedingly rare. Even if there are a dozen of them in the ~100 to 300 billion solar systems in the Milky Way, the vast distances mean that they will remain perfectly irrelevant (by being completely "out of reach") for humanity for hundreds or thousands of years, and possibly forever. Rather than being depressed that our childhood fantasies of exotic and fascinating extra-terrestrials are likely no less imaginative than any other world religion, let us savor the enormous fortuity of our existence, and that of our species and all Earthlings. In all the cosmos, it may well be that Earth is the ONLY true Garden of Life, and rather than being depressed by that speculation I suggest we need to be joyous. I believe if this ethos can be spread to even half of humanity, it might well progressively make us a more civilized and human species.

Recently, there has been much interest in Sol's closest known stellar neighbor, Proxima Centauri (4.224 light years away), owing to the August 2016 discovery of a near-Earth-sized terrestrial planet orbiting it within its "habitable zone," an orbital range within which the temperature could allow liquid water. However, some more recent analyses suggests that, the planets exposure to high-energy ultra-violet radiation probably means: No Earth-like atmosphere for Proxima b. Even more fascinating, just yesterday it was reported that ALMA discovered dust belts and an 'unkown source' around the star. In years past, I can recall the star being dismissed in terms of its prospects to host habitable candidate exoplanets, mainly because it is such small red dwarf star. In hindsight, clearly, we have not heard the last from Proxima Centauri! So I thought a general purpose thread to discuss the star and any future discoveries or analyses pertaining to it would be apt. For my purposes at this point, I'm curious about a couple questions: (1) How far would the "radiation kill zone" described in the "No Earth-like atmosphere" article extend out from the star? My physics is too elementary for me to know if the bad rads the article focuses on (apparently " high-energy extreme ultraviolet radiation" is the main culprit?) would have diminishing effects at any of the distances involved (e.g., "30 AU to the outer 'Cold Belt' described in the more recent ALMA discovery). (2) How large or potent of a magnetosphere would be required to "protect" Proxima b from the atmosphere-stripping effects described? (3) Are there geologically and cosmologically feasible processes which could shield a celestial body from the harmful rads described? For example, (and going entirely hypothetical here, not referring specifically to any features known about the Proxima system) could a moon orbiting a large parent (say Neptune) with a large enough magnetosphere be protected? Lastly, (4) I was edified some years ago when one of the more knowledgeable KSP forum members clarified that Jupiter is highly radioactive. I wonder if, under certain special circumstances, a combination of a star and a more proximal parent body might allow for surface liquid water on some moons somewhere out there? Yes I'm aware that several of the outer planet moons are thought quite strongly to have liquid water under large bodies of ice, but I'm just curious if a parent planet of "just right" configuration might emit just the right wavelengths (while not being a 'star' though perhaps toward the 'brown dwarf stage?) to keep a moon sufficiently warm and protected from cosmic radiation? -=-=- Beyond that, hopefully the thread might turn into a good multi-purpose general thread about the Proxima system! I appreciate anyone's comments or thoughts!

Recently got hold of "Children of a Dead Earth." Good stuff! Highly recommend if any of you guys are on the fence Actually wound up bopping in here because I am building a Helium-propellant driven Nuclear Thermal Reactor powered spacecraft and supplementing this very high exhaust velocity but relatively low thrust "Cruising" system with a much higher thrust Lox/Methane system (high dV and when needed, flip on the overdrive for maneuvers that require high acceleration). Did a search on the proper ratio of Lox to Methane and that google hit was actually THIS thread! I seem to be going in circles!

Hmmmm. You damn skeptics and realists . . . So what IS the most likely technology that the Kim dynasty will use to conquest space?

Hah! Good point What about nuclear pulse propulsion? That allows at least 0.2 if not 0.4 c (on paper) without any substantial "purely theoretical technology."

That fits with what I understood. I don't call that "direct observation." We can see the effects of something that must be there but we cannot see "it." Thus we observe dark matter, indirectly, which means, we really have no idea what it is. Merely that something is producing discrepancies in observed and expected observations. ADDIT: anyway, Dark matter and Dark Energy are (it seems to me) quintessentially about this thing we call gravity! Thus, it seemed to me that (a) the discovery of gravity waves; and (b) confirmation of that discovery by a different natural event might well have some implications for those theoretical constructs, with gravity being the central nexus of all three.

Directly observable how? What kind of telescope can "see" dark matter? I think you are using a different concept of "direct measurement" than I am. The fact it is called "dark" is indicative of the fact it is not directly observable is what I understood. It is a hypothetical force, whose presence is inferred based on the discrepancy of how galaxies SHOULD behave if the only matter present were that which IS observable (the glowing stuff) and how galaxies actually behave. Specifically, if the glowing stuff was all there was, galaxies should fly apart, so there must be other stuff we cannot see. I know about the lensing observations, but that too strikes me as "indirect" measurement of dark matter. The stuff itself still has not been seen, merely inferred with some precision based on the effects which "it" had on observable phenonenon. ADDIT: and I presume based on your screen name/title you are actually trained in physics (which I am NOT! ) so . . . please be patient with me. I'm not just trying to derail the thread or be a pain in the butt or otherwise disrupt discourse. I'm honestly just curious and want to learn more.

So what is dark matter "made of?" Where does it fit on the periodic table? We have yet to measure or observe it directly right? It is merely inferred based on discrepancies between expected and observed galactic configurations, right? I am most definitely no expert, but seems to me dark matter is still fairly hypothetical. Clearly there IS SOMETHING that accounts for the observations and the discrepancies which led to the invocation of the concept of "dark matter." But no one has yet to observe the stuff, no one knows for real what it is and it might be many things not merely one thing, eh? This merger involved gravity and confirmation of what appears to me to be a new if not revolutionary model of what gravity is, and the paradox of dark matter and dark energy all revolve around discrepancies in observed and expected behavior where gravity is a central parameter, so I still not convinced of "zero implications."

I thought the hypothetical phenomenon known as dark matter and dark energy had a lot to do with so-called gravity though?

It must be a truly fascinating time to be an undergraduate in physics with a thirst to push the envelope. I'm definitely too old for that sort of shenanigans . . . but you blew my mind with just the first few sentences which I put in bold. Might try to stomach that Veritasium video to get a digestible synthesis of it but . . . to put my central question to test: "Gravitational waves" isn't simply confirming that such a thing exists a gigantic "discovery?" What implications does this have for the whole dark matter/dark energy "we don't really understand 95% of the Universe" paradox?

What about lithium? Is it possible that there are chunks of lithium frozen out there in the Oort Cloud, and would it possibly be valuable?

You know . . . in a couple hundred years it does seem quite likely that there will be a major human presence off the Earth. Perhaps only thousands or tens of thousands of visitor/traveler/workers (maybe even "colonists"), but a significant presence nonetheless. Given the tremendous economic value (supposed) of some of the resources out there, it seems inevitable there will be plenty of human drama, even if one were to stick 100% to conservative estimates of how technology will work. Somebody really does need to make a game that covers that stuff.