Editing 2712: Gravity

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==Explanation==
 
==Explanation==
This interactive comic promotes Randall's new book [[What If? 2]], which was released in September and is available for purchase. You pilot a small spaceship throughout a vast area in space exploring various bodies and planets within the play area, many containing easter eggs alluding to the book What If? 2 and previous xkcd comics. The flight mechanics are Newtonian so the spaceship can use the gravity of planets to alter its trajectory or enter orbit. The spaceship has indicator circles around it which appear when a gravitational body comes into range, showing the direction towards their center of gravity and the size of the body. A circle also appears around the spaceship whenever it collides with a gravitational body, acting as a shield. The shield remains until the player orients the spaceship upright so its landing gear can deploy.
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This interactive comic promotes Randall's new book [[What If? 2]], which was released in September and is available for purchase. You pilot a small spaceship throughout a vast area in space exploring various bodies and planets within the play area, many containing easter eggs alluding to the book What If? 2 and previous xkcd comics. The flight mechanics are Newtonian so the spaceship can use the gravity of planets to alter its trajectory or enter orbit. The spaceship has indicator circles around it which appear when a gravitational body comes into range, showing the direction towards their center of gravity and the size of the body. A circle also appears around the spaceship whenever it collides with a gravitational body, acting as a shield. The shield remains until the player orients the spaceship upright so its landing gear can deploy.
 
 
This comic was the ground work for the next [[:Category:April fools' comics|April fools' Day comic]] of 2023: [[2765: Escape Speed]].
 
  
 
You can easily fly between planets if you pay attention to orbital mechanics: don't just floor the accelerator. The background stars show your velocity and orientation relative to the nearest gravity well.  If you are having difficulties navigating space, point towards a gravity orb and accelerate for only a few seconds. Wait until the background stars spin wildly, and then reduce your velocity to 0 before gently accelerating towards the object.
 
You can easily fly between planets if you pay attention to orbital mechanics: don't just floor the accelerator. The background stars show your velocity and orientation relative to the nearest gravity well.  If you are having difficulties navigating space, point towards a gravity orb and accelerate for only a few seconds. Wait until the background stars spin wildly, and then reduce your velocity to 0 before gently accelerating towards the object.
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|A reference to the question posed by ''What If? 2'' Chapter 13: Lose Weight the Slow and Incredibly Difficult Way. A large potato peeler is seen removing the earth's crust.
 
|A reference to the question posed by ''What If? 2'' Chapter 13: Lose Weight the Slow and Incredibly Difficult Way. A large potato peeler is seen removing the earth's crust.
 
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|}
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|'''Unknown Planet'''
 
 
 
<code>unknown</code>
 
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|(-63587, 9395)
 
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|
 
|
 
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|This location was not in the list. There is a non-escapable gravity object here.
 
<pre>Comic.voyager.pos
 
Object { x: -63587, y: 9395, a: 3.625954916940618, vx: 0, vy: 0, ax: 0, ay: 0, va: 0, aa: 0, isColliding: true, … }
 
</pre>
 
|-
 
}}
 
  
 
===Spaceships===
 
===Spaceships===
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==Trivia==
 
==Trivia==
* The objects in the mini universe of this browser game are all at fixed positions and do not interact through gravity, however, the ship controlled by the player is affected by gravity. While this makes it technically a relatively easy integration problem (of the position of the player ship forward in time), the integrator used seems to be a relatively simple one, but certainly not a simplistic one, because it does not conserve angular momentum. This can be seen when one manages to get into orbit around some object, e.g., the core of the sun. The orbit slowly decays over time.
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The objects in the mini universe of this browser game are all at fixed positions and do not interact through gravity, however, the ship controlled by the player is affected by gravity. While this makes it technically a relatively easy integration problem (of the position of the player ship forward in time), the integrator used seems to be a relatively simple one, but certainly not a simplistic one, because it does not conserve angular momentum. This can be seen when one manages to get into orbit around some object, e.g., the core of the sun. The orbit slowly decays over time.
 
 
* The logic for extending the landing legs and landing is rather simple. A ship can (normally) land if it is facing away from the surface it collides with, and if its momentum is more-or-less directed towards the surface. Once landing is triggered, the ship will rotate to face directly away from the object exerting the most gravity on the player, regardless of how sloped the surface is. The only way to get into space again is to accelerate forwards, as neither turning nor accelerating backwards cancels the landed state. All of this can be abused to land on almost everything. To land on the underside of an object, simply point your ship away from the object and slowly accelerate backwards to counteract the force of gravity. Landing on the side of an object is more difficult, as ships cannot accelerate sideways. The first method is to accelerate backwards to launch yourself upwards and towards the object so that at the top of your arc you will collide with the object. Then, rotate your ship accordingly to land. Method two is to just repeatedly slam your back of your ship into the object until you land. Note that with any of these weird landing methods, your ship will turn to face away from the source of gravity and can clip into objects.
 
  
* Executing <code>window.python("import antigravity")</code> or <code>python("import antigravity")</code> as Javascript on the page will reverse gravity, multiplying the gravity constant by -1.
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The logic for extending the landing legs and landing is rather simple. A ship can (normally) land if it is facing away from the surface it collides with, and if its momentum is more-or-less directed towards the surface. Once landing is triggered, the ship will rotate to face directly away from the object exerting the most gravity on the player, regardless of how sloped the surface is. The only way to get into space again is to accelerate forwards, as neither turning nor accelerating backwards cancels the landed state. All of this can be abused to land on almost everything. To land on the underside of an object, simply point your ship away from the object and slowly accelerate backwards to counteract the force of gravity. Landing on the side of an object is more difficult, as ships cannot accelerate sideways. The first method is to accelerate backwards to launch yourself upwards and towards the object so that at the top of your arc you will collide with the object. Then, rotate your ship accordingly to land. Method two is to just repeatedly slam your back of your ship into the object until you land. Note that with any of these weird landing methods, your ship will turn to face away from the source of gravity and can clip into objects.
  
* Executing <code>window.ze.goggles()</code> or <code>ze.goggles()</code> as Javascript on the page will show a warning in the console: "<code>they do nothing!</code>"
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Executing <code>window.python("import antigravity")</code> or <code>python("import antigravity")</code> as Javascript on the page will reverse gravity, multiplying the gravity constant by -1.
  
* Ponytail's comment on earth that she "checked downforeveryoneorjustme.com and it said just me" may be referencing the actual website at that domain, which checks if other websites are down.
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Executing <code>window.ze.goggles()</code> or <code>ze.goggles()</code> as Javascript on the page will show a warning in the console: "<code>they do nothing!</code>"
  
 
==Transcript==
 
==Transcript==
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Octopus: We've always used neutrinos for astronomy, but if we place my new "optical telescope" in orbit above the kryosphere, we could potentially observe the universe using electromagnetic waves.
 
Octopus: We've always used neutrinos for astronomy, but if we place my new "optical telescope" in orbit above the kryosphere, we could potentially observe the universe using electromagnetic waves.
 
 
Octopus: Who knows what else there is besides stars! There could be other worlds!
 
Octopus: Who knows what else there is besides stars! There could be other worlds!
  
=====Secret book club=====
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=====Secret book club hidden beneath the Unnamed sailor guy's ship:=====
  
 
Cueball: Does our book club really need this much secrecy?
 
Cueball: Does our book club really need this much secrecy?
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Megan to cueball: Jump in! The water's fine!
 
Megan to cueball: Jump in! The water's fine!
  
Knit cap: Ugh, the frame rate's really bad out today. (if you go in the rectangle containing the words, the whole game begins to stutter.)
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Knit cap: Ugh, the frame rate's really bad out today.
  
 
===Sun:===
 
===Sun:===
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Ponytail 2 to Cueball 2: In 5 billion years, the sun will run out of fuel & suffer gigential burnout.
 
Ponytail 2 to Cueball 2: In 5 billion years, the sun will run out of fuel & suffer gigential burnout.
  
===Dogplanet:===
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{{comic discussion}}
 
 
Cueball: I want more dogs!
 
 
 
dog 1: Ball! Again!
 
 
 
dog 2: I hope it lands soon.
 
 
 
Ponytail: English adjective order means that you're "Clifford the big red dog" but not "Clifford the red big dog"
 
 
 
Cueball to Ponytail: You can't have too many dogs!
 
 
 
===Quantz:===
 
 
 
Gardener: Welcome ... to Jurassic park.
 
 
 
===Enterprise:===
 
 
 
Ground text: U.S.S. Enterprise
 
 
 
Ground text: NCC-1701-C
 
 
 
===Greatattractor:===
 
 
 
Ground text: The Great Attractor
 
 
 
Ground text: The Great Attractor
 
 
 
Ground text: The Great Attractor
 
 
 
Ground text: The Great Attractor
 
 
 
Ground text: The Great Attractor
 
 
 
Ground text: The Great Attractor
 
 
 
Ground text: The Great Attractor
 
 
 
= Page Discussion =
 
Due to the length of this article, the [[Talk:2712: Gravity|Comic Discussion]] is not fully transcluded here.
 
 
 
 
[[Category:Space]]
 
[[Category:Space]]
 
[[Category:Book promotion]]
 
[[Category:Book promotion]]
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[[Category:Comics with lowercase text]]
 
[[Category:Comics with lowercase text]]
 
[[Category:What If?]]
 
[[Category:What If?]]
[[Category:Popular Comics]]
 

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