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She Blinded Me With [Science] Thread

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  • PsykomaPsykoma Registered User regular
    3clipse wrote: »
    Yeah I dunno what he was up to during his hiatus but I'm sure glad he's back.

    He was hired as the chief of research and development at buzzfeed and I think he's still there. Dunno why he decided to go back to making true facts, though I'm grateful.

  • XehalusXehalus Registered User regular
    what if it's a giant frozen clump of alien shit that got jettisoned but missed it's destination of star disposal

  • bowenbowen How you doin'? Registered User regular
    Xehalus wrote: »
    what if it's a giant frozen clump of alien shit that got jettisoned but missed it's destination of star disposal

    are we talking about life on earth or..

    not a doctor, not a lawyer, examples I use may not be fully researched so don't take out of context plz, don't @ me
  • BahamutZEROBahamutZERO Registered User regular
    Fun Space Fact: Throwing garbage into a star is actually pretty hard, it takes a ton of energy to lower the orbit that far

    BahamutZERO.gif
  • Donovan PuppyfuckerDonovan Puppyfucker A dagger in the dark is worth a thousand swords in the morningRegistered User regular
    Fun Space Fact: Throwing garbage into a star is actually pretty hard, it takes a ton of energy to lower the orbit that far

    It's crazy to me that we could fire a Saturn V directly at the Sun and it would probably miss completely.

  • DedwrekkaDedwrekka Metal Hell adjacentRegistered User regular
    I think I remember reading something that said that the entry velocity of a body is equal to the escape velocity.

    IIRC it was talking about why railguns wouldn't work as orbital bombardment weapons.

  • Donovan PuppyfuckerDonovan Puppyfucker A dagger in the dark is worth a thousand swords in the morningRegistered User regular
    Dedwrekka wrote: »
    I think I remember reading something that said that the entry velocity of a body is equal to the escape velocity.

    IIRC it was talking about why railguns wouldn't work as orbital bombardment weapons.

    I read that orbital bombardment would be best achieved with a network of satellites, all firing telegraph pole-sized cylinders of tungsten at the celestial body they are orbiting so that the gravity of the body pulls them down to the surface at hypersonic speeds. The impacts from objects so heavy at such speeds would be MUCH more powerful than most atomic bombs. I think that was in an old issue of Popular Mechanics?

  • BahamutZEROBahamutZERO Registered User regular
    there's a scott manley video illustrating that concept in kerbal space program:

    https://www.youtube.com/watch?v=m0Cun9hp_B0

    BahamutZERO.gif
  • Al_watAl_wat Registered User regular
    I mean, if you are orbiting something and you want to get to the surface you don't thrust directly at the surface. You thrust retrograde, i.e. in the direction opposite of your orbital vector

  • BahamutZEROBahamutZERO Registered User regular
    Yeah due to the way orbital mechanics work, to deorbit you need to slow down enough that your orbit shrinks to intersect the planet surface, or at least enter the atmosphere and then slow down enough from the air friction. The velocity this happens at is fixed because your orbit's altitude is determined by your orbital velocity. This applies to projectiles fired from a railgun just as much as it does spacecraft, meaning there's an upper limit on how fast something reentering the atmosphere from an orbit around Earth can be going. The reason 8-ton tungsten rods work is because while the fixed velocity they have as they deorbit is relatively low, they have waaay more mass than a railgun projectile, which work by having low mass but relatively high velocity from being launched out of the gun. Energy = 1/2 * Mass * Velocity.

    However you can also cheat by having an orbit around some other body that then intersects with the target planet. Then you can be going ridiculously high velocity relative to the thing you're impacting. That's how asteroids and such can be a threat.

    BahamutZERO.gif
  • DedwrekkaDedwrekka Metal Hell adjacentRegistered User regular
    Dedwrekka wrote: »
    I think I remember reading something that said that the entry velocity of a body is equal to the escape velocity.

    IIRC it was talking about why railguns wouldn't work as orbital bombardment weapons.

    I read that orbital bombardment would be best achieved with a network of satellites, all firing telegraph pole-sized cylinders of tungsten at the celestial body they are orbiting so that the gravity of the body pulls them down to the surface at hypersonic speeds. The impacts from objects so heavy at such speeds would be MUCH more powerful than most atomic bombs. I think that was in an old issue of Popular Mechanics?

    That idea has some of the most awesomely terrifying sounding names attached to it.
    "Rods of God"
    "Kinetic Kill Vehicle"
    "Thor shot"

  • TynnanTynnan seldom correct, never unsure Registered User regular
    Dedwrekka wrote: »
    Dedwrekka wrote: »
    I think I remember reading something that said that the entry velocity of a body is equal to the escape velocity.

    IIRC it was talking about why railguns wouldn't work as orbital bombardment weapons.

    I read that orbital bombardment would be best achieved with a network of satellites, all firing telegraph pole-sized cylinders of tungsten at the celestial body they are orbiting so that the gravity of the body pulls them down to the surface at hypersonic speeds. The impacts from objects so heavy at such speeds would be MUCH more powerful than most atomic bombs. I think that was in an old issue of Popular Mechanics?

    That idea has some of the most awesomely terrifying sounding names attached to it.
    "Rods of God"
    "Kinetic Kill Vehicle"
    "Thor shot"

    "The Overcompensator"

  • PlatyPlaty Registered User regular
    edited November 2018
    Dedwrekka wrote: »
    I think I remember reading something that said that the entry velocity of a body is equal to the escape velocity.

    IIRC it was talking about why railguns wouldn't work as orbital bombardment weapons.

    I read that orbital bombardment would be best achieved with a network of satellites, all firing telegraph pole-sized cylinders of tungsten at the celestial body they are orbiting so that the gravity of the body pulls them down to the surface at hypersonic speeds. The impacts from objects so heavy at such speeds would be MUCH more powerful than most atomic bombs. I think that was in an old issue of Popular Mechanics?

    There are different sizes and classes of utility pole but the standard pole in the US is twelve meters long and has a base diameter of 32.258 centimeters (let's ignore that utility poles get thinner towards the top). A tungsten cylinder of that size would weigh 75.7 metric tonnes - which is six tons more than the empty weight of the Space Shuttle orbiter (but the Space Shuttle orbiter would also carry equipment and fuel).

    For the drag coefficient, let's assume the cylinder is encased in a streamlined sheath which also protects it from aerodynamic heating and stabilizes it. I'm however still going to use the projected area of the Tungsten cylinder.

    Calculating terminal velocity gives us a maximum speed of 9621.44 meters per second at sea height. Coupled with the mass of the tungsten cylinder this gives a kinetic energy of 3.5 TJ. Which is immense but still falls short of atomic weapon yields. Castle Bravo's yield was estimated at 63 PJ or 63000 TJ of energy.

    Platy on
  • PlatyPlaty Registered User regular
    edited November 2018
    I haven't put any thought into whether the cylinder can fall long enough from orbit to reach its hypothetical terminal velocity. As it moves through the air, the cylinder would transfer energy to its surroundings, but intuitively I wouldn't expect catastrophic effects for anything on the ground. I also assumed a perfect heat shield so the cylinder doesn't deform.

    Meteoroids typically enter Earth's atmosphere at speeds in excess of over 20 km/s.

    Platy on
  • discriderdiscrider Registered User regular
    edited November 2018
    Platy wrote: »
    I haven't put any thought into whether the cylinder can fall long enough from orbit to reach its hypothetical terminal velocity. As it moves through the air, the cylinder would transfer energy to its surroundings, but intuitively I wouldn't expect catastrophic effects for anything on the ground. I also assumed a perfect heat shield so the cylinder doesn't deform.

    Meteoroids typically enter Earth's atmosphere at speeds in excess of over 20 km/s.

    These things tend to tumble too.
    A easier approximation is probably to just drop giant titanium balls onto the planet instead.
    Then you don't have to work out fins or something.

    discrider on
  • BahamutZEROBahamutZERO Registered User regular
    you put some small fins on one end and they won't tumble

    BahamutZERO.gif
  • Donovan PuppyfuckerDonovan Puppyfucker A dagger in the dark is worth a thousand swords in the morningRegistered User regular
    you put some small fins on one end and they won't tumble

    Shit, just mount the rockets that fire it away from the satellite in such a way that they cause it to spin like a bullet, and it'll be fine.

  • furlionfurlion Riskbreaker Lea MondeRegistered User regular
    Hmm this makes me think, does the stabilizing effect of the rotation do anything outside of an atmosphere? I know the reason for the spin is to reduce tumbling due to the way bullets are fired. With a rocket powered, or even gravity powered, projectile you could account for that tumbling in a different manner, especially with a larger surface area to work on. Surely one of you fine people know?

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  • TynnanTynnan seldom correct, never unsure Registered User regular
    furlion wrote: »
    Hmm this makes me think, does the stabilizing effect of the rotation do anything outside of an atmosphere? I know the reason for the spin is to reduce tumbling due to the way bullets are fired. With a rocket powered, or even gravity powered, projectile you could account for that tumbling in a different manner, especially with a larger surface area to work on. Surely one of you fine people know?

    Yes, inertia will do its thing regardless of atmosphere. We routinely use spin to stabilize space probes.

  • PlatyPlaty Registered User regular
    edited November 2018
    discrider wrote: »
    Platy wrote: »
    I haven't put any thought into whether the cylinder can fall long enough from orbit to reach its hypothetical terminal velocity. As it moves through the air, the cylinder would transfer energy to its surroundings, but intuitively I wouldn't expect catastrophic effects for anything on the ground. I also assumed a perfect heat shield so the cylinder doesn't deform.

    Meteoroids typically enter Earth's atmosphere at speeds in excess of over 20 km/s.

    These things tend to tumble too.
    A easier approximation is probably to just drop giant titanium balls onto the planet instead.
    Then you don't have to work out fins or something.

    A sphere has ten times the drag coefficient of a streamlined body and a higher projected area. Muskets and cannons used to fire round projectiles but those were more affected by air resistance.

    Of course you can also consider the "problem" of the tungsten object in a different way: it can't impact with more energy than was expended by transporting it into orbit. The amount of fuel needed would be similar to the fuel consumed by the Space Shuttle. And while that is a lot of chemical energy, it's not much compared to what nuclear weapons can produce.

    Platy on
  • BahamutZEROBahamutZERO Registered User regular
    edited November 2018
    it is very very expensive to set up compared to even non-nuclear conventional weapons with similar effects yeah

    BahamutZERO on
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  • SiliconStewSiliconStew Registered User regular
    edited November 2018
    Platy wrote: »
    discrider wrote: »
    Platy wrote: »
    I haven't put any thought into whether the cylinder can fall long enough from orbit to reach its hypothetical terminal velocity. As it moves through the air, the cylinder would transfer energy to its surroundings, but intuitively I wouldn't expect catastrophic effects for anything on the ground. I also assumed a perfect heat shield so the cylinder doesn't deform.

    Meteoroids typically enter Earth's atmosphere at speeds in excess of over 20 km/s.

    These things tend to tumble too.
    A easier approximation is probably to just drop giant titanium balls onto the planet instead.
    Then you don't have to work out fins or something.

    A sphere has ten times the drag coefficient of a streamlined body and a higher projected area. Muskets and cannons used to fire round projectiles but those were more affected by air resistance.

    Of course you can also consider the "problem" of the tungsten object in a different way: it can't impact with more energy than was expended by transporting it into orbit. The amount of fuel needed would be similar to the fuel consumed by the Space Shuttle. And while that is a lot of chemical energy, it's not much compared to what nuclear weapons can produce.

    It's not just the drag, if the sphere starts spinning, the Magnus effect can make it curve away from its intended trajectory. It's why round-ball muskets were inaccurate.

    SiliconStew on
    Just remember that half the people you meet are below average intelligence.
  • FishmanFishman Put your goddamned hand in the goddamned Box of Pain. Registered User regular
    edited November 2018
    This reminds me of my brief sojourn with Syndicate Wars, the not-very-good sequel to the original Syndicate 90's game.

    In the first game, the most fun was had by opening up the cheat codes to equip your dudes with the best equipment and gear and just blow through missions in ridiculous murderfests. So when I got the sequel, the first thing I did was unlock high tech gear and enough cash to equip my dudes with a dozen copies of the most expensive weapons.

    Wandering through the first missions, I handily murdered my way into a bit of a firefight with some opponents. The game did this thing where when you selected a weapon, a disembodied female voice would announce the change. "Minigun". "Uzi".

    I clicked on the most expensive weapon - most expensive must be best, right? - and went to move my targeting reticule over the enemy, but no reticule appeared. "Satellite Rain" said the silky female robot voice. Was it broken? I clicked again. "Satellite Rain. Satellite Rain. Satellite Rain." Still no reticule.

    Then the world exploded.

    Because as you may have realised, Satellite Rain was not a gun, but a request for geosynchronous Tungsten-Uranium rods to be deployed from orbit to your current position, with about a 20 second delay to get out of the way.

    And I had just ordered a half dozen of them. And hadn't moved.

    Naturally, my dude was a smear on the pavement. As was a roughly 3-square-block surrounding area.

    I gave playing shortly after that; the game wasn't that fun and nothing I ever did was going to be as stupidly fun as that again.

    But yeah, once I got over the shock of seeing an entire screen turn white and go up on smoke and then after that stop laughing, I now hold a nostalgic place in my heart for orbital bombardment and a silky digitised female voice saying the words "Satellite Rain".

    EDIT: I also now tend to RTFM before clicking on anything, just in case it's one of those buttons that calls down several Terajoules worth of radioactive molten metal to where you're standing, for instance.

    Fishman on
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  • Al_watAl_wat Registered User regular
    you guys all need to play some Kerbal Space Program

    seriously I learned so much about orbital mechanics from that game.

  • 3cl1ps33cl1ps3 I will build a labyrinth to house the cheese Registered User regular
  • tynictynic PICNIC BADASS Registered User, ClubPA regular
    shut up everybody

    we just found something weird in Canada, and it isn't @ChicoBlue

    https://www.cbc.ca/news/technology/hemimastigotes-supra-kingdom-1.4715823
    Canadian researchers have discovered a new kind of organism that's so different from other living things that it doesn't fit into the plant kingdom, the animal kingdom, or any other kingdom used to classify known organisms.

  • 3cl1ps33cl1ps3 I will build a labyrinth to house the cheese Registered User regular
    https://www.nature.com/articles/s41586-018-0708-8 <-- article

    1) Cool as heck.

    2) "Here we report phylogenomic analyses based on high-coverage, cultivation-independent transcriptomics" I have serious, serious questions about why they sequenced the transcriptome and not the genome. Perhaps those will be answered when I am back at work on Monday and can read the full article.

  • webguy20webguy20 I spend too much time on the Internet Registered User regular
    tynic wrote: »
    shut up everybody

    we just found something weird in Canada, and it isn't @ChicoBlue

    https://www.cbc.ca/news/technology/hemimastigotes-supra-kingdom-1.4715823
    Canadian researchers have discovered a new kind of organism that's so different from other living things that it doesn't fit into the plant kingdom, the animal kingdom, or any other kingdom used to classify known organisms.

    omb1aq16xd3p.jpg

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  • ShadowenShadowen Snores in the morning LoserdomRegistered User regular
    edited November 2018
    tynic wrote: »
    shut up everybody

    we just found something weird in Canada, and it isn't @ChicoBlue

    https://www.cbc.ca/news/technology/hemimastigotes-supra-kingdom-1.4715823
    Canadian researchers have discovered a new kind of organism that's so different from other living things that it doesn't fit into the plant kingdom, the animal kingdom, or any other kingdom used to classify known organisms.

    Will this anti-Newfie prejudice never end?

    Shadowen on
  • BroloBrolo Broseidon Lord of the BroceanRegistered User regular
    Peas wrote: »

    so i skimmed the video but from what I gather is weight is whatever we want it to be

    and so technically i'm no longer overweight

    and therefore its okay, perhaps even scientifically recommended, for me to eat this entire family size bag of ruffle brand gravy'n'onion flavored potato chips for breakfast

  • Al_watAl_wat Registered User regular
    edited November 2018
    Brolo wrote: »
    so i skimmed the video but from what I gather is weight is whatever we want it to be

    and so technically i'm no longer overweight

    and therefore its okay, perhaps even scientifically recommended, for me to eat this entire family size bag of ruffle brand gravy'n'onion flavored potato chips for breakfast

    Frankly it is against the laws of science not to eat that.

    Al_wat on
  • DisruptedCapitalistDisruptedCapitalist I swear! Registered User regular
    Can someone explain how those species are different from animals?I mean, they eat other organisms, isn't that what animals do? Or am I missing something with how they suck out the innards of bacteria being not quite "eating?"

    "Simple, real stupidity beats artificial intelligence every time." -Mustrum Ridcully in Terry Pratchett's Hogfather p. 142 (HarperPrism 1996)
  • BahamutZEROBahamutZERO Registered User regular
    eating is not what defines something as an animal

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  • BahamutZEROBahamutZERO Registered User regular
    edited November 2018
    https://en.wikipedia.org/wiki/Kingdom_(biology)#Kingdoms_of_the_Eukaryota

    Huh I guess the kingdom animalia is no longer a thing, instead animals are considered part of the kingdom Opisthokonta together with fungi. And plants are now in the kingdom Archaeplastida. Nooo my high school biology textbooks are obsolete!!!

    Anyway these creatures simply fit in a new kingdom under the domain of eukaryota. They share a common ancestor with the rest of us eukaryotes more recently than with the domains of archea or bacteria, but far enough back to deserve their own branch on the family tree.

    BahamutZERO on
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  • DisruptedCapitalistDisruptedCapitalist I swear! Registered User regular
    edited November 2018
    Ugh. You're going to make me look it up aren't you. I'm so damn lazy.

    Ok, here we go from wikipedia:
    Animals are multicellular eukaryotic organisms that form the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development.

    Huh, more requirements than I thought, but consuming organic material is one of them.

    Edit, oh I looked up "animals" but I didn't notice that they're not even a kingdom anymore. That actually makes more sense now with the new discoveries. Cool!

    DisruptedCapitalist on
    "Simple, real stupidity beats artificial intelligence every time." -Mustrum Ridcully in Terry Pratchett's Hogfather p. 142 (HarperPrism 1996)
  • BahamutZEROBahamutZERO Registered User regular
    edited November 2018
    the features like "eating" and "breathing oxygen" aren't really the main requirements, they were just the only things people had to base guesses about relationships between organisms on before genetic comparisons were possible. Now it's based more on actual ancestry relationships learned from DNA analysis, where possible at least.

    BahamutZERO on
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This discussion has been closed.