Talk:2011: Newton's Trajectories

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Actually he's talking about ICBM's that have the potential to end civilisation in fire if actually launched, not the crash of a spaceship.141.101.107.156 04:39, 25 June 2018 (UTC) Agreed, the object emitted from the cannon is either a rocket or an ICBM. 172.69.158.46 04:51, 25 June 2018 (UTC)

Couldn't he be talking about the rocket being mistaken for whatever big bomb we use right now and start the whole mutually assured destruction gig? I hear that there have been a lot of close calls/radar malfunctions/whatever whatevers that almost sent us into the apocalypse. Come on, Didn't Germany write a song about that? (Granted, it's apparently the show of force that starts the war, but you guys get my point) 172.69.33.233 05:42, 25 June 2018 (UTC)

I am German and didn't write a song on that issue. The song that comes closest for me is Fylingdale Flyer by Jethro Tull.
Ninety-nine red balloons (https://en.wikipedia.org/wiki/99_Luftballons) by Nena - 108.162.219.148 08:02, 25 June 2018 (UTC)
Neun Und Neunzig Luftballons, to say the title of the original German version in its native tongue.
ProphetZarquon (talk) 17:54, 25 June 2018 (UTC)
I find it unlikely that the comic refers to an accidental crash, and more intentional use. If we're launching something into space on a trajectory aimed at some distant part of the Earth, it isn't for non-fiery death purposes.

I was surprised to see the quote 'slip the bonds of earth' on a circular orbit. This seems pretty bound to earth. Wouldn't it have made more sense to include a parabolic escape trajectory? --Quantum7 (talk) 10:01, 25 June 2018 (UTC)

Except (as far as we know) Newton never considered parabolic trajectories. Whether he did or didn't, the original diagram didn't show anything beyond a circular orbit. Mr. I (talk) 12:36, 25 June 2018 (UTC)
Maybe because the hard part is attaining a stable orbit. Once you do that, it's relatively trivial to escape it. Indeed even the orbit itself, while being determined by Earth, can be considered an escape since you will never again come back to Earth as long as that orbit is maintained. So Randall may have considered that close enough to talk about escaping the bonds of earth (which the stable orbit accomplished) and traveling to the stars (which is the logical next step; or at least to moons and planets so far in our case). -boB (talk) 15:03, 25 June 2018 (UTC)
See this What If? question: https://what-if.xkcd.com/58/ 172.68.46.191 00:18, 28 June 2018 (UTC)

When Jane's Defence discusses strategic (read: nuclear) weapons systems, they do not distinguish between satellite delivery vehicles and ICBM launch vehicles. The only differences are the trajectory and the payload. This comic is definitely about satellites and ICBMs. I'm new here, sorry if I'm not signing this properly --OtherBarry--

Fiery death is also mankinds's future if we remain passive and refrain from destroying ourselves, since the sun will eventually grow to engulf the earth. (Solar Evolution) So the comic is not necessarily as pessimistic as some may think. However, he leaves out the possibility of civilization ending in a non-fiery way before this event. 198.41.230.10 16:48, 25 June 2018 (UTC)

Note that for this comic the launch angle is near vertical and for all cases the object launched is steered in flight to the final trajectory. For Newton's canonball the ball was launched horizontal to the local Earth surface from a high mountain. A canonball launched vertically appears to be acted on by "forces" when seen from the Earth frame of reference. These "forces" depend on the launch site, altitude and velocity of the object - they are due to the rotating frame of reference. Baring atmospheric resistance, the only true forces on the ball after launch is gravity. But it is certainly true a ball fired vertically from anywhere but the poles does not land back at the site of launch due to the rotation of the Earth. For canon available in Newtons day corrections to aim were not necessary but by the late 1800's big guns were firing projectiles far and high enough that corrections for Coriolis forces were required. Corrections were pre-calculated for range and firing direction for whatever theater of war the gun was being used.