JoeSchmuckatelli

I don't know. We've exactly two probes that have gotten that far, and everything I've seen is speculation. I certainly would not assume anything like the illustration provided - as, yeah, the interstellar media would have to be relatively 'stationary' rather than co-orbiting. I've always perceived the heliopause as simply the region where the solar wind can no longer make the atmosphere exclusive to Sol - and if that's the case, the interstellar media is likely to be more dominated by the local environment of stars than some wind from the center of the galaxy... So I picture something more like a hazy bubble than a comet trail - we've all seen bubbles drifting with the wind: they're not perfect spheres, but they don't trail like that

Alright - so just going back to xyz coordinates - let's say that I had a second-series (prequel) Star Wars FTL drive (almost instantly get to where you want to go, unlike the original trip taken in the Millennium Falcon) and wanted to visit another galaxy, far, far away... Is there any real way to predict its physical location today? Because if the light we see today from two different galaxies can take different paths that both last 500, 000 years, but be wildly different 'straight line' distances from the Milky Way today... How could you know you would arrive at your destination and not just somewhere random? Thanks for including links! Now I have tonight's reading planned! And seeing as we believe that we are starting to detect black holes merging... https://www.nbcnews.com/science/space/biggest-bang-big-bang-scientists-detect-collision-huge-black-holes-rcna106 Do you know of anyone looking into the data for Kerr type catastrophes?

This is one of those things I can't just learn once. I 'know' the answer - but again, it's such a brain twist I have to keep revisiting the concept. Here's a weird question - so what is time, then, other than the movement and curving of space? Does it have any independence from space or does Einstein have them inextricably entertwined?

So... if we say then, that another galaxy is x light years away from the Earth... that's not really an absolute measure of distance... I can't multiply 186,000 miles/second to get a number of miles that would mean anything - i.e. two 500 ly away galaxies might not actually be equidistant from the Earth - the light from one might have to pass through a relatively dense part of the universe, whereas the light from the other goes through a void? Edit: although (brain twist) maybe it is?

If space and time are intertwined, and mass compresses space and time, do we say that the speed of light is the same in the presence of a massive object as it is in the intergalactic void because the ruler has changed?

Surprisingly, Google translate did a fair job of translation.

Have the death star blow up the world? Message: time to die

... And these last few posts are why I read these forums!

The answer to the question of how many people you can fit into a telephone booth in an emergency is: "One More"

You have no idea how many short people fetishize playing basketball. There is literally no way to get out of the whole story on 'if I had your height... Maaaan I'd be in the NBA - - why this one time in middle school..." It never ends James Cameron did a piece with subs and NASA types trying to game out how to do underwater exploration of a place like Enceladus. It was pretty cool... And they talked explicitly about how very deep oceanic exploration is similar to space exploration... And done a lot less

I (literally) LOL'd Fiction has to be believable, but Nature can do whatever the heck she wants! Oh - and I have another Science - type question... Suppose someone, somehow, was able to pull off a 'Space Battleship Yamamoto" - type thing; would all that steel be a benefit in space or would it somehow become a radiation hazard? (I have a vague recollection of reading something about a manned Mars ship needed to be built in a way to mitigate inter-planetary radiation... and that steel wasn't a good candidate)

Here's a sciency question: can you blow out long enough during an emergency ascent to prevent getting the bends?

So if I might opine: the purpose of combat is different than what most people assume. As I wrote above, it is but one method of untying a political knot. One of the tools in the nation-state (or other political actor's) kit-bag. Ultimately, however, the solution sought is (and has to be) a political resolution. The problem is that people are stubborn. Sometimes they don't want to do what you want them to do... and thus, if you want them to do something bad enough - and they resist, your only recourse is to knock a few heads. So as you recognize, when you have an enemy and have decided to engage him in combat, you want to defeat his will to fight more than anything. You want him to have a way to accept defeat as the lesser of two evils. Again, people are stubborn, so this can be difficult. Especially if you want to 'stay on the right side of history'. i.e. not randomly killing women and children or destroying civilian infrastructure or religious buildings. All of these limits that you set for yourself going into a conflict make that particular conflict more difficult - but actually makes your broader political goals more attainable, and future conflicts easier to manage. For a concrete example: when we went into Iraq in 03, we had a very strict set of rules we had to follow. These included not firing upon civilians or religious institutions or cultural locations. This meant that we restricted our use of many weapons systems during heavy urban combat - accepting higher risk to ourselves - because the Iraqi soldiers and Fedayeen showed no qualms about hiding in these spaces or shooting at us from them. I'm not exaggerating when I say that our combat experience in the cities was harder than it needed to be, because of our own restraint. But I witnessed first hand the benefit of that restraint. Not two days after some of the heaviest fighting in one of the cities, we were approached by a group of civilians. They offered to return some of the personal items of Marines who had died in the city, showed us to their graves - respectfully dug, and watched calmly as we recovered them. The civilians asked us if we were actually serious this time about eliminating the Sadaam government (and the man himself). They accepted our answer... and offered us this: they would give the Fedayeen three days to leave town, or they would kill them themselves. To @SOXBLOX's points: approaching combat, you have both strategic goals and tactical considerations. Smart planners will keep the larger political goals in mind, even down to the Company level. So yes, at one point you might want to take down a rail-yard to prevent the enemy from easy troop movements - but maybe you dont want to destroy the hydro power dam and send floodwaters crashing down on an industrial city. Again, if you wantonly destroy everything the enemy holds dear, what exactly are you winning? The problem comes when you look at a protracted war between nations relatively equal in power (with every type of power one might consider) - when you have parity between combatants, you can get into some ugly brawls, especially when your political goal is the unconditional surrender of your opponent. And as @DDE wrote - expecting a knock-out blow to work is rarely successful. I saw a woman, well-versed in Jiu Jitsu fight a man who was both taller and larger than she. She fought him to submission and choked him out. Rather than realize he'd been beaten, every time he came to he jumped up wanting to fight some more. Had others not broken up the fight, she might have been forced to kill him. As the Japanese learned in Pearl, unless you overwhelmingly succeed with your 'knockout'... you just end up liquiding (*) off your opponent. What made Hiroshima and Nagasaki successful was that they came at the end of the war - they showed that not only were we willing to fight to the end, but that we had the capacity to do so with little risk to ourselves. At that point, our exhausted enemy accepted defeat as the lesser of two evils. (*if you really want to twist your noggin, think about the devastation caused by the firebombing of Dresden and Tokyo, and then ask yourself what would have happened if instead of being used in 1945... we'd dropped bombs in 1942 - when our enemies were feeling rather spry. I submit that we'd not have seen only two cities nuked) Heck - even the Empire and its successor state saw this: using the Death Star(s) just liquided people off even more. Instead of being scared, they got angry. And an angry human is a dangerous thing. (*) this is a 'creative' edit by the language filter... I may have to use it myself sometime!

Very true. While I wrote 'food' in general, I I should have specified that I meant a high variety and access both to quality and quantity of proteins - milk farming / herding provides both. Early farmers generally had less variety (I. E. Mostly rice or mostly wheat), but the plenty and stability allows them to have more children. Trade, on the other hand, ameliorates quite a bit of the problems of early, isolated farming communities. Hence Catalhoyuk & etc - once you have enough cities, the hunter gatherers get pushed into wastelands. @kerbiloid mentioned replenishing trees as a fantastic resource for developing peoples... And that's true. The American Midwest to the East coast enjoys similar climate - lots of rain and broadleaf forests. The major problem for the indigenous North Americans was the lack of large domestic animals for work. The other thing that was mentioned was need. The massive drought drove innovation in Central Asia - while competition drove it in Europe. I often wonder if plenty might also play a part in the fact that African and North American native technologies did not proceed apace with Eurasia, and whether plenty can explain the difference in post 1200s innovation between Europe and Asia. Both North America and Africa have /had plenty of game and in certain places relatively easy farming conditions. Asia, after the Mongols became relatively stable. Absent an environmental need or massive competition for resources... Those peoples did not have to innovate as fast. Fast forward to today - and plenty in the West seems an issue. There is a lot of innovation and competition coming from the Asian (including India) part of the world. It will certainly be interesting to see how this all shakes out

I see that that is at least partly sourced from SCMP - would you mind sharing a link? Also of interest is why they're associating food sources / farming methods with social behavior. Always interesting to read how people see themselves and analyze the differences they perceive between themselves and their neighbors. Along with what @kerbiloid writes / posted below, you guys have provided info into another area of fascination of mine, specifically human development and migrations. Lines like "Thanks to them, the Papuans are tall" makes me itch to get out the e-shovel and start digging! The pilaf is also making me hungry! I love that stuff! BTW - I'm mentally sticking my tongue out at you with your, "produces a stable whirl they call cyclone" - because, of course it does. I should have recognized that. Nyeeah! I'll also agree that there is some evidence that larger body mass confers advantage in cold climates - but I'm not certain that that the climate theory is wholly proven or required. Yes, in northern Europe we get a bunch of very tall people, but that does not entirely extend to those living in the actual arctic. Similar studies indicate that being large (Polynesia) or tall (Africa) conferred advantages related to food scarcity (travelling long distances across open water) and surface area to sweat/cool the body (hot open plains). But as in the link I posted above - milk proteins in diet seem to be strongly correlative with stature as well (many Asian people are naturally lactose intolerant given that their ancestors didn't rely upon milk as a regular food source). https://www.sciencedirect.com/science/article/pii/S1570677X16300065 Whereas in Europe milk consumption (especially in the north) is fairly common. An interesting thing I spotted in this article was the relative heights of the 'tall' folks (170's cm range). Those are current heights. We like to think of ourselves as taller now than our ancestors, but it does look as if pre-Ice Age folks were quite tall as well: https://www.pnas.org/content/116/43/21484 Food seems to have such a strong correlation with height, in fact, that hunter-gatherers who enjoyed a wide variety of foods, despite no regular food source were often taller and healthier than early farmers who relied upon a limited but stable supply: https://www.discovermagazine.com/environment/early-farmers-were-sicker-and-shorter-than-their-forager-ancestors Meaning that Conan really would have scared the heck out of the farming villagers he met! .

I'll add to what @SOXBLOX wrote: in the space-warfare genre, the escape pods take the place of life rafts on past and present warships. As someone who's been on a present-day warship in a contested zone, I actually appreciated the Navy having them on board, because if things went bad, I'd have at least a second chance at life... and where there's life, there's hope. There are a lot of misconceptions about warfare - such as 'killing everyone'. There is no need, as a combatant, for me to kill all of the enemy. I simply have to defeat him; and there are ways short of death to do that. (in fact, having a reputation for 'killing everyone' is actually counter-productive toward your desire to defeat the enemy: Absent some thought that they can successfully surrender, your enemy will literally fight to the death, taking at least some of your forces with them). Ambrose Bierce* described War as "Untying a political knot with the teeth, that would not yield to the tongue" - and this is true, especially in the West, and more-so since the industrial revolution. European (including ancient Roman) traditions have very few cases where the victor put everyone to the sword, salted the earth and ethnically cleansed an area c.f Carthage. It happened, but it wasn't common. In the East (including Russia), historical mass killings were more common, comparatively, but still unusual. More often the defeated were turned into slaves, serfs, vassals or hostages - without simply killing everyone, or even every soldier. So, in the space-war concept, putting life-boats / escape pods on your warship does two things; it gives the sailors, soldiers and Marines 'a sense' that they get a second chance, and if necessary actually does; with the caveat that unless rescued they're at a minimum going to be prisoners, or at worst lost/abandoned, killed by the enemy or even eaten... but they can console themselves that they didn't die with the ship. (Grim humor, sorry) Which brings me to your Star Wars analogy; Lucas invented the ultimate terror weapon with the Death Star; a super-analog to the Nuke. The problem is, that any self-respecting galactic empire needs all the planets it can get, and unlike a nuke, zapping an entire planet into rubble is a colossal waste. Hiroshima and Nagasaki are still cities. They're economically viable. Alderaan isn't. And the subsequent stories building a second Death Star and Planet Killer Base and all the other escalation, for me, wasn't good story-telling. It was too simplistic, almost pedantic. I far more enjoyed the various battleships, landers and etc. An Empire that occupies and controls is believable. An Empire that wantonly destroys is not. * https://en.wikipedia.org/wiki/The_Devil's_Dictionary#:~:text=The Devil's Dictionary is a satirical dictionary written,a series of installments for magazines and newspapers.

Thanks for the explication!

Wild Donkeyed Guess - but are you referring to entanglement or some other thing of which I'm blithely unaware?

I'm insufficiently familiar with China to know this, but did the source for this provide any explanation for the differing heights? E.g. availability of high quality and varied food, food scarcity, relative poverty or ancestral group? A 10 cm spread that is as geographically distinct as shown between the shorter south and the taller, coastal north is intriguing. Well - wouldn't that be largely determined by land and water distribution? Hard to have a cyclone if your tidally locked 'face' is an enormous, high desert plateau (he wrote, realizing that all of this is speculative given the lack of habitable, tidally locked planets with atmospheres in our current knowledgebase) It gets annoying after a while. People either ask or assume I was a basketball player, even though I'm built like an aging lineman. I mean, I never ask people if they're jockeys

I've enjoyed reading the question and subsequent answers - but I have a follow on question: presuming a rigid 1ly bar that doesn't collapse under its own gravity... Would the inertia be such that both ends could move simultaneously - or does 'suppose-itional' physics require compression at one end followed by a speed of sound transmission to the far end before the movement can occur?

Great - now I'm hungry. (Thankfully I have two pieces of grass-fed Ribeye sitting in the fridge and a pellet grille on the back porch)

Very interesting article came out recently (http://www.bbc.com/travel/story/20200823-why-are-the-dutch-so-tall ) about why the Dutch are so tall. Lots of dairy and exercise. It references a time when Americans were the tallest on the planet (we've been bypassed) - and part of it had to do with 'breeding rates' of the population. Tall dudes in Holland get the 'average sized' girls and breed quite often, while, currently in America, the highest breeding rate is among those men Cruise can cruise with... and again 'average sized' women... (Edit Whoops - got this wrong; see below) but mostly its about the food Oddly enough, I've actually read that a child's greatest predictor of adult height is actually the Mother's relative height. (Apparently, this is anecdotal, b/c the easily discoverable references are mostly pap) But yeah - access to both plentiful and varied foods is a predictor of size; look at what's happened in China (incl HK) and the other highly developed Asian countries over the last 75 years as food scarcity has largely become a thing of the past https://www.scmp.com/news/hong-kong/health-environment/article/1994996/tall-tales-asians-hit-new-heights-largest-growth Edit: oh and another anecdote: When I visited Germany in 1994, despite being markedly taller than pretty much everyone I met in Europe (as in America) - folks assumed I was German when we met. Apparently there's lots of tall there too. What always trips me up, however, is when I say 'yeah, I'm pretty much the tallest person here (wherever 'here' may be) -- Invariably I run into two people who are taller still!

In the same way that Tom Cruise's contracts stipulations say he can't be portrayed as short? 8D RU tanks are not comfortable for most folks - a 6'2" dude would be unhappy (but Cruise would be fine)

At 6'7", I found the M1a1 to be a tight squeeze with the Flak jacket. No way I could get in with the SAPI plates we were told to wear... But once inside it was quite comfortable (and way better than any ballistic insert). What killed me was trying to get into a Challenger 2, when we ran into some Brits and played you show me yours I'll show you mine in Kuwait. Fit through hatch? Check. Room to move inside? Check. Close the hatch in case of arty or rain? Nope. Apparently only American tanks accept tall people. Discrimination, if you ask me!

I've got him beat. Marines are thick skulled and hard headed. Navy ships are harder