Green Baron

Everything our findings tell us speak against the notion of "galactic empires". It is nice movie stuff but not more. We can't survive in space, the stars don't have the necessary materials, we can't afford the energies necessary, we can't achieve the speeds. Even comparisons with the past tell us that such a thing as a uniform spreading of culture over the earth or even a continent where there is everything to make a living does not exist. There is not a single scientific hint that any one of the assumptions in the OP has a root in reality. No signs of "advanced societies", no uniform growth, few comparable species' lifetimes, only nice pictures. I had to say that :-)

Lemmyhelp: besides the dioxins and charcoal, if made from white industrial bread isn't that healthy at all ....

That is absolutely true. Abri (overhanging cliffs) or rock shelter is the right word, the "termius technicus" or technical term. Though mostly kept secret among archaeologists in order not to take the chance to work as a consultant for Disney and the likes. The poor guys always need money :-) Seriously, ritual places could be added as an explanation, deducing from paintings and from parallels to shamanism the walls of caves might have had a meaning for the late ice age people. I am sure there is info about it to be found. But i don't want to disrupt the colourful depiction of our future with boring narrations from the past

Hehehe. Everybody tested their calculators :-)

You mean, we don't necessarily need space for this to happen ? :-)

I stumbled upon this: http://www.nejm.org/doi/full/10.1056/NEJMoa1705129 tl:dr: Degeneration of the brain leads to losses of cognitive abilities in long term space flights. Just f information, i cannot judge the relevance.

Oh, was it 05:35 ? Local or gmt ? Sorry, mind the time @cratercracker, the example is for 22:30 local time !

I see. For your orientation: Does it look familiar ? :-) You must project this to a sphere. Capella will be right above your head, the blue line is the horizon without any obstacles, so Orion leaning 45° to its left, Sirius very low under it, maybe blocked by trees or so.

Then your picture is somewhat distorted. First, as @YNM pointed out, the sky over a metropolitan area like Moscow will only show a few main stars. Second, at this time of the year all the heatings are running at night, which makes the air over the city flicker heftily (what you described). @YNM, people like us can't imagine, but the poor guys have -C degrees. Heatings run, chimneys spit out hot glimmering air, there is a mixed up bubble of air over a city like Moscow. Orion should be low in the southern sky at that time in Moscow, leaning to the left. Have a look at Wikipedia of how it looks, you should at least be able to identify Beteigeuze (one of the few clearly red/orange stars in sky) and the blue/whitish Rigel, the girdle stars might be too faint. There is another one nearby that, if it rises above the horizon (try to find out yourself ;-)), is easily identified, and that is Sirius. It is simply the brightest star in the sky. Orion is not small, the distance between Beetlejuice and Rigel is a little more than the hang loose gesture.

Geology professor in one of the introductory lectures on earth's internal dynamics. The guy was a few months before his retirement and didn't take everything too serious any more. 3 short sentences = 60 million years. "... the oceanic crust draws from the middle oceanic ridge towards the continent, cooling and getting denser until it is heavy enough to rip off from the continental crust and dive into the mantle. Because it cooler and denser than the surrounding mantle it tears ever more oceanic crust after it, thus closing the ocean, until it gets so heavy that a slab rips off. The overlying continental crust, held down by all the weight, suddenly springs up and there ... you have a mountain range like the Alps."

Uncertainties are no strict limits. They describe were the probability curve gets so flat that it looses significance. The probability curve is computed based on the current knowledge and estimations of the figures that contribute to it. Apparently overlap allows for the above interpretation. But sure, many theories need refinement and corrections, including measurement of star's magnitudes, colours and relative speeds. And not all processes inside a star are understood in detail, which allows for speculations about their dimming for example, or the rate with which they burn their material. I surely don't always believe all that Nasa says, but in this case i'd say that the star can still get younger (it was guestimated 16by before) and the universe can get older (even cosmological constants have shown a rate of change in the past ...). I'd rather bet on the star having some leeway for younger dates. *shrug*

Well, the measurement uncertainties put the star well within current theories. From the nasa site about the star: "Hubble data and improved theoretical calculations were used to recalculate the star's age and lower the estimate to 14.5 billion years, within a measurement uncertainty of plus or minus 800 million years. This places the star within a comfortable range to be younger than the universe." http://hubblesite.org/news_release/news/2013-08/56-hubble-telescope The universe can stop scratching its head, its children are all younger than itself :-)

@sevenperforce: this may be a silly question and this is all a silly discussion but wouldn't we only hear those sn's that fled from us with subsonic speed ? Acoustic redshift sotosay ? Those closer would kill us anyway before we "hear" something.

It has been 18°C max. the past days and rainy. Today again 24°and sunny. Min temp. early morning 16°. Summer is over ...

Yeah, this is a question that hasn't yet been solved. The human brain is 2* the size of that of comparable mammals and enabled us (or should i say them :-) ?) to complex problem solving. https://www.nature.com/articles/nature11380 http://www.sciencedirect.com/science/article/pii/S0166223608002099 Evolution is apparently not always a steady path, sometimes new arrangements appear and are not immediately sorted out. Edit: i am not a creationist ! But, maybe soon(*) this question isn't that important any more since with the late Neanderthals and early modern humans the maximum size apparently was reached. It is shrinking again. Fun fact ? (*) a few hundred generations.

Well, just one more reason why you can't hear it ... :-) Zeros do matter I'd rather have mine with garlic, please ?

Soft. [ˈdɔːdʒe] Like in job or jambo ! (Bwana) Edit: if you mean the Italian lord ... ? ... oh, you probably don't. Just realized OP's avatar ... ignore me.

If only things where so easy :-) There's an ocean full of water on earth. You can't drink it. You can hardly gain enough for one person by evaporation at sea level in an atmosphere as thick & thirsty as earth's. Morning thaw must come to the rescue in humid climates if you have something to collect it, but it isn't always there when you need it. Shipwrecked can and do actually die of thirst surrounded by slightly (3% !) salted water. Now take soil that has 3% water. Higher concentrations are suspected i think, but somebody or something should actually take a look as to the wheres and hows. Btw., there is plenty of water below the earth's deserts, yet nobody lives there and at the fringes, where some do live, they pump until the ground water level gets out of reach. To wash the cars, those i... forget it :-) Forget evaporation on Mars, you'd need something like osmosis to produce water (see: watermaker for ships), which in the same turn might help parting with some of the bad stuff. But it needs a lot of electricity and, despite your claims, it might and probably is just not enough for housekeeping and these things are very maintenance intensive. I would say unsuited for a distant planet. But don't cite me left handed :-))

What we all suspected but did not dare to admit has been proved: Video gaming changes structures in the brain, and not to the best. http://onlinelibrary.wiley.com/doi/10.1111/adb.12570/abstract;jsessionid=B003A4C519C369B3E431EF706F1961C6.f02t02 Okay. So be it

If you tell us where (Moscow), when (date and time) and the location (direction and height above horizon) then we might help. Also, try one of the numerous online planetariums and skymaps (example: http://skymaponline.net/). The flickering has nothing to say, it's simply movement in the atmosphere, very strong above cities naturally. If you say "very small", here's another hint: the thumb on a stretched arm is about 1°, the fist about 10°, "hang loose" about 15°.

i am sure it is on the list of potential future landing and probing sites. Patience we must have :-)

Between 5 and 60% and it's almost nothing, absolutely spoken ;-) We've been there ...

Very good example, the Thresher tragedy. The investigation revealed major construction flaws like no clear difference between "inside" and "outside". A broken pipe of 2cm can fill a compartment in seconds under that pressure. Much was learned. Having a similar disaster in space with a BFS because some basic things weren't thought of would throwback space exploration for decades because public perception would suffer greatly.

I suggest anyone who thinks a suitport is a handwavy thing embarks on a sailing trip, let's say 6 days on the Atlantic, in a 14m sloop (that's bigger than most Atlantic crossings can afford). Suitport is the head because no saltwater suit gets into the cabins or even behind the companionway. You'll never have dry clothes again otherwise. After 2 days the plastic suits start to smell, they are wet and they don't dry. After 3 days you start to hold your breath when taking the jacket on. But there are three more days. And if it is your wake, you dress it and go out, in rain, sun, waves whatever. And there is breathable air, you can scratch your nose or your back if it itches. Oh, and when your wake is over you enter down and hang your stuff between that of others. See above. Try it out, then judge it. Source ? That is the dream for the far future. It is unknown if there is enough water and if it is obtainable. Air ? A source would be nice. And you need everything close (a few hundred meters), not water from the poles and air from equator ;-) Doesn't exist. Is being thought (dreamed ?) about. Trivial, the effects of interplanetary radiation as well as that of particles is largely unknown. "Hide between the stuff" is only a helpless excuse until more is known. Only a few people have been outside of earth's magnetic field for a few days. Eh ? Again, grammar matters: will have to be fixed by humans ;-) and for most the fixation will have to be researched :-)

Submarine and ISS can be evacuated should all go wrong. A submarine can also run to the next harbour or call for help should something vital happen, so vital has a much larger margin than a manned spaceship. There is no such possibility for a ship that travels to Mars. If there is no redundancy then almost any larger failure can have grave consequences. An accident like Apollo 11 for example would mean death for everybody on board. Many of the probes we sent have had failures, in the attitude control, the instruments on board, the propulsion, etc. I don't know the percentage, but it is significant. The only consequence is that the mission objective is adjusted accordingly. Electronics don't mourn. A manned ship would be as thoroughly built as possible but, as we know, bad things happen and cannot always be calculated, even in every day's course. I see the next step as NASA has planned with the station around the mun, to check the technology, the influence of interplanetary environment. ability to plan and execute answers to unscheduled events. With more routine the picture will become clearer. Musk wants to skip these steps and go directly on the journey, which in my eyes is a recipe for disaster.