Diche Bach

yes . . . 0.05 c my bad HOPE is not a strategy!

Ah looks like I need to get in on this. Have you guys eliminated Proxima b or are you among the "hope beyond hope" crowd? ADDIT: Imagine the drama in this thread in 10 or 20 years when they finally get James Webb out there and peering at the atmospheres . . .

Thank you! Damn . . . 0.5 c for an arrival trip to Trappist (39 light years distant) is 780 years! Even Alpha Centauri and Proxima Centauri (~4.4 light years, which are probably pointless from an "habitable target" standpoint) are 88 years! ADDIT: looking at that link at the projectrho site . . . came upon the design for the URSS Alabama . . .http://www.projectrho.com/public_html/rocket/slowerlight.php#id--Go_Fast--Starships Thas what I'm talkin' bout! ADDIT: and just to clarify: the "0.5 c for a rendezvous journey (i.e., not a "fly-by" but a "slow down to arrive and enter orbit at target system")" for an "Orion-style" external nuclear pulse propulsion design . . .this is a result of the tradeoff between mass and energy capacity? Bombs, blast absorption plates, shock absorbers, life support apparatus, etc., etc., all have "minimum mass" values established by existing materials science (and reality!). One could carry more bombs in order to try to go faster, but at the 0.1 c threshold one reaches the point where: existing bomb yields are insufficient and carrying more bombs to allow for longer period of acceleration/deceleration just doesn't work? So . . . less massive materials, more powerful bombs (per bomb mass), else some means to "multiply" the propulsive force of each bomb (like e.g., an energy field projected along the surface of the blast absorption plate that was calibrated to have repulsive reaction to the polarity of the blast wave?) could all increase the total viable velocity?

Neat! The last thing I read about the Starshot conceptions was referring to a velocity about half of that, and I want to say a laser power demand a lot more powerful than that too; seems like what I was reading suggested that the total energy cost to send Starshot on its voyage would have consumed a large fraction of humanities total annual energy supply, but I might simply be confusing things, or their estimates might have improved. It looks like actual annual human energy consumption is in the 109,500 Terawatt hours per year ballpark. So one Gigawatt relative to that doesn't seem so large. https://en.wikipedia.org/wiki/World_energy_consumption Looks like the largest momentary power output so far achieved is ~2 petawatts for a tiny time span http://en.yibada.com/articles/50471/20150802/japan-blasts-worlds-most-powerful-laser-beam.htm Not sure how long Breakthrough Starshot needs to be blasted at 1 Gw to get to 0.3 c, but apparently it is in the realm of posibility! However, propelling a nano-craft to 0.3 c and propelling a robot craft much less a manned starship are very different prospects. My layman's understanding is that: the energy required to propel a space craft in the 4000 t size range (the size range used in many of the Project Orion modeling from the 1950s) using laser sail would literally require more energy than the sum total of all humanity has ever created . . .or thereabouts . . . So, it seems to me that while the use of lasers to propel tiny survey probes is quite promising it is unlikely to result in technologies which can send sizeable spacecraft for a very long time, if ever.

Well, it is "energy dense," so the idea I had in mind with my layman's physic was: project an energy field "behind" one's space craft that would have a "repulsive" response to the polarity of the CME. Buckle up and let Repulsion serve as your Propulsion!

What is the fastest velocity humanity could achieve for a spacecraft with 2018 technology? Excluding all 'speculative' technology, i.e., limiting to technology based strictly on accrued physics, what is the maximum velocity we could currently achieve? I have specified "manned" specifically to exclude miniaturized technologies like Breakthrough Starshot, which obviously can go faster but with enormous constraints on payload. What method(s) of propulsion could be used? Given this is a spacecraft, I suppose the velocity would be relative to either Earth or the Sun. Based on what I presently understand, 0.1 c (around 29.9 million km/s) using nuclear pulse propulsion seems to be the fastest with technology that is possible in principle; though whether the technology could actually be made to work is impossible to say without trying. My main reason for asking is: some years ago I had reviewed the topic and reached the conclusion that the fastest actually feasible was with external nuclear pulse propulsion and that this technology might be able to achieve speeds in the 0.2 c ballpark. I recall a web site or series of websites I found with rather detailed and seemingly rigorous fairly recent (late 1990s or early 2000s) analysis and synthesis which built off of the Project Daedalus and Project Orion stuff, but included some additional corrections based on more modern bomb and materials technology. I want to say this was a University of Pennsylvania research groups page, but it seems to have evaporated now. My recollection is that, improvements in materials and bombs since the 1950s, and 1970s analyses are what accounted for the doubling in achievable velocity, but it may be that my memory is faulty and I'm just confusing make-believe stuff (like fusion containment, or antimatter powered) with straight up bomb-surfing "can do it if you got the money and willing to ignore the treaties" technology. Appreciate any help on clarifying this. I'm at the point in writing up my timeline where I need to know, and while the difference between 0.2 and 0.1 is arguably 'not that great' my goal is to keep things as close to diamond-hard hard science fiction as possible for as much of the imagining as possible . . . Oh, and btw, money is no object; nor are flimsy things like "treaties," human-rights, or "risks" All I need to know is: what is the LEAST fanciful 'fastest speed we can do with present physics technology,' and given no constraints in terms of money or ethics.

Well even with the question of propulsion set aside, I'd say we are decades if not a century from any serious prospects of interstellar. Any vessel of any size will have be assembled in space and clearly we need something a lot more substantial than the ISS for something like that.

Hmmm . . . Seems a lot better than what we have managed so far. I've got our best controlled speed achieved so far as being the Juno probe which achieved 76 km/sec, so 3200 km/sec ~42 times faster. Seems that would still put a one way trip time to Alpha Centauri around the 4,000 years ballpark. Lots better than the 168,000 years it would take a "Juno speed" spacecraft, but still not very practical. Once again: nuclear pulse propulsion seems to be the only real hope . . .

Would it be possible to create a technology that allowed a space craft to "surf" on a coronal mass ejection?

Heisenberg and Schrodinger are speeding down the highway when a state cop pulls them over. The cop walks up to the window and asks Heisenberg,"Do you know how fast you were going?"Heisenberg replies, "No, but I knew where I was."The cop says, "You were going over 90 miles per hour!"To which Heisenberg replies, "Fine. Now we're lost."Thinking this answer is a little strange, the cop decides to investigatethe vehicle. He begins by opening the trunk. Shocked by what he finds, he shouts, "You have a dead cat in here!"Schrodinger answers, "Well I do now!"

There is another concept, that is particular apt for Indie developers: expansion and refinement. As a pure engineering simulator, the application is shockingly good. As a game, its pretty bad. What would make it a better game? More and more significant choices for the player. What would those choices hinge on? Could be many things, including "whom to ally with versus prey upon," but even if the players allegiance and role within the game world is unchangeable, economic choices and logistics are an obvious area for introducing choice for the player. That is basically all a 4x game is, and while this one doesn't quite fit the bill of a 4x, it could easily adapt some of the design elements to, as I said, achieve the games full potential. I'm not criticizing the game, I'm simply pointing out how it could achieve a helluva lot more by leveraging what it already has in spades. Given the dude is obviously scary smart, and industrious (he made that application!) then I don't see what the big deal would be to introduce better game play.

Touched a nerve? I don't make the "rules" about how national level military and science undertakings work; I'm just here to state the obvious. Engineering never occurs in ideal circumstances. Economy and logistics, as well as demand always play strong moderating (if not mediating) roles in technological development. The same is even more true for military operations. Dude doesn't necessarily need to hire anyone. Code Force (effectively one guy) managed to portray a convincing and engrossing galactic ecology/economy and a system of logistics and resource management in Distant Worlds Universe.

Sounds good. What about logistics, and economy? Without those, the game will never achieve its full potential.

Isn't this "Space Force" declaration really just explicating and "officializing" a long historic series of military in space ventures which have existed since the 1940s? That is my take on it.

I like to hope that we ARE the "Precursors" that are so commonly portrayed as being the "original" high-tech "lost civilization" that left traces of their intergalactic web in so many flavors of sci-fi, and (to insure that sentience never dies) left retro-virus like codes in simple biota seeded across the multi-verse so that it would eventually, billions of years later evolve into all the humanoid-esque alien forms . . . We are just infantile Precursor's still! When we can at the right moment in our organic life cycle undergo the "The Uploading" and become one with the galactic information network, we will have arrived at early adulthood

What makes you think they never built any megastructures or colonized land or space? In seriousness though . . . I know a reasonable amount about primate psychology, a smidgen about canine psychology, and a tiny bit about animal psychology in general. From my standpoint, most prevailing notions/models/theories of "intelligence" are quite stupid because, not only do they focus only on a limited range of human mental function, they focus almost exclusively on human mental function. Bat echolocation; geese migrating; cetaceans doing all their crazy long-distance stuff out in the oceans; fungi networks communicating up and down the entire length of the Appalachians . . . obviously none of these things are quite the same as our unique human ability to grasp symbols and syntax and combine them in creative ways to exchange mental states with other human beings. But how other animals manage the wonders which they do with ease is largely obscure to us, and much of our own thinking is clouded with imperfections. The fact that we evolved into "sentient" beings might well have never occurred anywhere else in the entire history of the universe, and might never occur again. That is how random and unlikely it looks to me based on my understanding of what is well established about human evolution and evolutionary psychology.

Cool. Good stuff. Great video. Kurg is doing Galileo's work there, teaching the willing masses about science

"Efficient" in what sense? Because if all the material and energy and maintenance that are required to create a solar panel and the amount of energy it produces is compared to the virtually "free" energy contained in a field of kelp or some other reasonable unit of photosynthesizing, I'd be impressed if the solar panel can actually compete . . . at least in the sense of the actual energy "captured" by the two methods. Harvesting the energy in the kelp field might turn the advantage over to the solar panel, but that just means we gotta figure out how to better get the energy out of autotrophs!

Uhh . . . given that nothing escapes a black hole, how could one consider it to be an "energy source?" ADDIT: and going back to the question to which you responded "What is the most efficient way to use the sun?" What about photosynthesis? Is anything actually "more efficient" than that?

What a lovely planet. A real vacation spot.

Yep! Good points. In any event, thanks for the feedback guys! Watch out Harry Turtledove! Here I come!

Good stuff Intriguing that Szilard's thinking was 'sparked' by Wells Sci Fi . . . and that suit though!

Wow . . . So ~1825-26 Photography: https://en.wikipedia.org/wiki/Photography#Invention_of_photography Taxonomy of elements: https://en.wikipedia.org/wiki/Periodic_table#History sounds like that was more or less a constant "work in progress" from 1790s through till the 1970s! There really IS value to thinking outside the box it seems. Imagine if the prevailing standards of today (negative results are almost never worth publishing) had held true in 1887 and the Michelson-Morley experiments null results had not been published

I don't think spacecraft or rover production volumes are sufficient to "host" a true "planned obsolescence" design and marketing philosophy. Rather, as others have stated in more indirect terms: these projects are about designing to meet specifications and reduce unintended bad outcomes. In order for planned obsolescence to be an advantageous strategy there needs to be a high enough volume that future needs are highly probable.

So, to you guys who are buffs or experts on this stuff: why did they send rovers to Mars without a radioisotope generator? That tech is like what . . . 45 year old? Was it just cost? It seems it was always pretty obvious Mars is a dusty place, and thus solar power was problematic