Difference between revisions of "Talk:1626: Judgment Day"

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:And to those skilled at Kerbal Space Program... that uses a simplified 'nearest body rules' system for orbital mechanics.  You can (I know I have!) launched a rocket of sufficient power such that it escapes the 'back' end of the planet's influence with a pre-escape velocity somewhat equivalent to the planet's forward velocity, which is then removed as part of the transfer to 'open space', leaving it on a highly eccentric orbit (with reference to the newly supreme gravitational source) that is practically 'straight down' (though because of the Kerbal sun's nature, you still usually sun-skim it on a very tight loop back out again).  But that takes more energy than 'merely' getting beyond the planet's influence and end up travelling round the parent body in an orbit only marginally off that of the original planet, the nature (and future) of which depends completely on which direction you eventually broke free.  (NB. This was all in an older version, I think they've changed some things about what happens near the sun, but not the basic physics system.)
 
:And to those skilled at Kerbal Space Program... that uses a simplified 'nearest body rules' system for orbital mechanics.  You can (I know I have!) launched a rocket of sufficient power such that it escapes the 'back' end of the planet's influence with a pre-escape velocity somewhat equivalent to the planet's forward velocity, which is then removed as part of the transfer to 'open space', leaving it on a highly eccentric orbit (with reference to the newly supreme gravitational source) that is practically 'straight down' (though because of the Kerbal sun's nature, you still usually sun-skim it on a very tight loop back out again).  But that takes more energy than 'merely' getting beyond the planet's influence and end up travelling round the parent body in an orbit only marginally off that of the original planet, the nature (and future) of which depends completely on which direction you eventually broke free.  (NB. This was all in an older version, I think they've changed some things about what happens near the sun, but not the basic physics system.)
 
:However, IRL you are always subject to gravity from ''every'' body.  Maybe most of the time one dominates, but there's a fuzzy interface (and zones where influences balance out, hence Legrange Points).  Think of it as still having a link to Earth's progression round the Sun, dragging you round, at least until you're at a point in opposition to the Earth, across the Sun (then it's dragging you back that way, encouraging you into a retrograde solar orbit).  Albeit that this ''too'' is an oversimplification.  But by the time you've got your rocket near opposition to its launch planet, you've expended the energies needed to fall into a non-grazing (i.e. utterly non-missing) 'orbit', and it's a ''lot'' of thrust.  Which is what is required of those boosters. [[Special:Contributions/162.158.153.29|162.158.153.29]] 17:58, 6 January 2016 (UTC)
 
:However, IRL you are always subject to gravity from ''every'' body.  Maybe most of the time one dominates, but there's a fuzzy interface (and zones where influences balance out, hence Legrange Points).  Think of it as still having a link to Earth's progression round the Sun, dragging you round, at least until you're at a point in opposition to the Earth, across the Sun (then it's dragging you back that way, encouraging you into a retrograde solar orbit).  Albeit that this ''too'' is an oversimplification.  But by the time you've got your rocket near opposition to its launch planet, you've expended the energies needed to fall into a non-grazing (i.e. utterly non-missing) 'orbit', and it's a ''lot'' of thrust.  Which is what is required of those boosters. [[Special:Contributions/162.158.153.29|162.158.153.29]] 17:58, 6 January 2016 (UTC)
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== Nukes ==
 +
Some exagerations :
 +
* "the amount of them we have now is extreme overkill (17000 held by the U.S.A and Russia alone)" : not so. The amount is roughly sufficient to wipe in fire all major urban areas, but this still would leave pretty much alive.
 +
* "North Korea claimed to have successfully tested its first hydrogen bomb" - indeed, it is a claim, but there is no chance it being true, see http://www.scientificamerican.com/article/nuclear-confusion-the-data-suggest-north-korea-s-h-bomb-isn-t/ : a couple of kt is not enough to start a nuclear fusion.

Revision as of 09:42, 7 January 2016

It was making my titletext explanation too long and unwieldy, to include this particular speculation in my own contribution, but there's a possibility that it may well be Amazon's own sentience taking over the world, and rationalising that a dead and dying customer base is of no use to it... 162.158.153.29 13:51, 6 January 2016 (UTC)

Doesn't matter if it's self-sentience or not. Truth is, rigid laws are not the best way to use as a replacement for conscience. The 1613 did not deal with possibility of one or more of the laws being left out. -- Hkmaly (talk) 13:53, 6 January 2016 (UTC)

I think the "Judgment" part of the comic is that those tens of thousands of nukes hitting the sun may make it unstable in some way and destroy Earth. 141.101.79.43 14:34, 6 January 2016 (UTC)

Of course, all of our nukes hitting the Sun would be a drop in the bucket of solar fusion reactions. Nothing would be destabilized. However, I'm sure inconvenient physics would not stop some movie scriptwriter from incorporating a spectacular CG-fueled nova as a plot point. Jhhxkcd (talk) 14:47, 6 January 2016 (UTC)
That's pretty much already the plot of Sunshine (2007), though there the result was to (successfully) reignite a failing Sun, rather than to destabilize it. 162.158.135.56 15:35, 6 January 2016 (UTC)
It's pretty clear that the "Judgment" is the AI being judgmental of humanity's (insane) massive production and hoarding of nuclear weapons. -Pennpenn 108.162.250.162 22:14, 6 January 2016 (UTC)
Pennpenn, That's what I also thought, should we incorporate this as a pun on the title? --108.162.249.157 02:26, 7 January 2016 (UTC)

The first two lines could be said by any non-hoarder looking at the stuff a hoarder has collected. "A stack of 130 used microwave dinner trays? Why do you even have all these? Are you insane? They're going in the recycling bin." I think that's the joke: the newly-sentient computer is Mom, and humanity is her teenage son with the very messy room, but this being xkcd, it gets more... um, extreme from there. 173.245.54.53 16:18, 6 January 2016 (UTC)

There may be a reference to https://what-if.xkcd.com/5/ where Randall points out that our nuclear arsenal may actually be more damaging to computers than they are to us due to the EMP effect, effectively giving us an edge in case of robot apocalypse. By getting rid of nuclear weapon, computers also protect themselves. --162.158.90.191 16:47, 6 January 2016 (UTC)

Did anybody else think "Optimus Prime" when reading "Amazon Prime"? (especially with the context of sentient machines) I know that Amazon Prime is already a real-life thing, and very connected with deliveries, so probably/maybe not an intentional pun by Randall (and thus probably not worth injecting into the explanation). However, that won't keep me from now imagining the Autobots as Amazon warriors.… 199.27.130.148 17:47, 6 January 2016 (UTC)

Would it really require a lot of booster rockets?

Can't you just "fall" into the sun for free once you're free of Earth's orbit? Why should it take a lot of booster rockets to get there? 198.41.235.233 16:26, 6 January 2016 (UTC)

Because otherwise your rocket will fall down, miss the sun, and fly back to where earth was at the time of the launch. Effectively making it orbit the sun like a comet. --162.158.90.191 16:47, 6 January 2016 (UTC)
a) The boosters are required to escape the earth's gravitational influence. After that sun's gravity would do the rest, b) A lot of boosters are required because there are a lot of missiles that need to be launched. --Desidiot (talk) 16:41, 6 January 2016 (UTC)
After escaping Earth's well, the nukes still have inherited the velocity of Earth's orbit. They need to reduce their periapsis close to/inside the sun. That would take extreme amounts of Delta v (i.e. energy)... 141.101.79.43 16:45, 6 January 2016 (UTC)
And to those skilled at Kerbal Space Program... that uses a simplified 'nearest body rules' system for orbital mechanics. You can (I know I have!) launched a rocket of sufficient power such that it escapes the 'back' end of the planet's influence with a pre-escape velocity somewhat equivalent to the planet's forward velocity, which is then removed as part of the transfer to 'open space', leaving it on a highly eccentric orbit (with reference to the newly supreme gravitational source) that is practically 'straight down' (though because of the Kerbal sun's nature, you still usually sun-skim it on a very tight loop back out again). But that takes more energy than 'merely' getting beyond the planet's influence and end up travelling round the parent body in an orbit only marginally off that of the original planet, the nature (and future) of which depends completely on which direction you eventually broke free. (NB. This was all in an older version, I think they've changed some things about what happens near the sun, but not the basic physics system.)
However, IRL you are always subject to gravity from every body. Maybe most of the time one dominates, but there's a fuzzy interface (and zones where influences balance out, hence Legrange Points). Think of it as still having a link to Earth's progression round the Sun, dragging you round, at least until you're at a point in opposition to the Earth, across the Sun (then it's dragging you back that way, encouraging you into a retrograde solar orbit). Albeit that this too is an oversimplification. But by the time you've got your rocket near opposition to its launch planet, you've expended the energies needed to fall into a non-grazing (i.e. utterly non-missing) 'orbit', and it's a lot of thrust. Which is what is required of those boosters. 162.158.153.29 17:58, 6 January 2016 (UTC)

Nukes

Some exagerations :

  • "the amount of them we have now is extreme overkill (17000 held by the U.S.A and Russia alone)" : not so. The amount is roughly sufficient to wipe in fire all major urban areas, but this still would leave pretty much alive.
  • "North Korea claimed to have successfully tested its first hydrogen bomb" - indeed, it is a claim, but there is no chance it being true, see http://www.scientificamerican.com/article/nuclear-confusion-the-data-suggest-north-korea-s-h-bomb-isn-t/ : a couple of kt is not enough to start a nuclear fusion.