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xkcd #2898: Orbital Argument
(imgs.xkcd.com)
Alt text:
"Some people say light is waves, and some say it's particles, so I bet light is some in-between thing that's both wave and particle depending on how you look at it. Am I right?" "YES, BUT YOU SHOULDN'T BE!"
And that point is inside the sun.
No actually. Due to Jupiter, the centre of mass of the solar system is actually very slightly outside of the sun
Leave it to Jupiter to mess yet another thing up
Stupid lazy ass diabetus planet doesn't even have enough mass to fuse its hydrogen.
Wouldn’t the center of mass constantly be shifting by the planets’ varying positions in orbit?
Yes, but it's mostly shifting because of Jupiter. It's just so dang heavy. Like, a couple times heavier than every other planet put together. I don't have the brain wattage to do the cool math right now, but a quick google search says that while the barycenter of the solar system does depend on all the planets, more often than not, it is outside the sun
Easy reminder:
sun ~ 10^30 kg
jupiter ~ 10^27 kg
earth ~ 10^24 kg
so the ratio is always 1000:1
relative to the center of the Milky Way, yes.
Sadly, the quantum foam has no gridlines.
So doesn't that mean the earth and sun do not orbit a common center but a varying point based on mostly Jupiter?
Centrists have bamboozled me again!
Cool. I learned something today
But I think the math of the argument is only about the common center between Earth and the sun, taking away all other planets out of the equation, especially Jupiter.
No the comic is pointing out that the sun and the earth are both orbiting the milky way galactic center.
Edit: While also true, I was wrong, they orbit the center of mass of the two body problem (earth and sun). I still think that's too simple of a way to look at it. It's not a two body problem and the other planets and the whole galaxy are also in play.
I mean technically every body in the entire universe exerts gravity on everything else as long as it's in your light cone
What's a light cone?
A not too heavy cone.
https://en.wikipedia.org/wiki/Light_cone
this doesn't give a very good explanation but I'm sure there's some good YouTube video that breaks it down. essentially maps out everywhere in space and time that could possibly interact with you in any way. this maximum is represented by how fast light can move away from you.
for example if you stole my car and ran away from me, I can draw a circle on the map every hour for how far you could have gone (assuming I knew my car's maximum speed). if I put those circles on top of each other it'll make a cone.
True in reality it's just the sun and Jupiter orbiting each other in a common point...
Inside the sun lol.
Wait I'm sorry, are we saying that the earth's orbit isn't almost entirely dictated by the gravitational pull of the massive star at the center of our solar system? I am a simple man, I apologize if that is a stupid question.
When dealing with gravitational systems the gravity of each object has to be taken into account. So even though the sun is 99.999% (hyperbole) of the gravity in the equation, the earth’s gravity contributes that small 0.001% and thus the “center” of where they orbit isn’t truly the center of the sun. Tack on Jupiter, which is much more than a fraction of a percent and that “center” moves even farther away from the middle of the sun.
To look at it further, if you had two objects of perfectly equal mass and no other gravitational interference, they would orbit around a point in the middle of each other since their pull is equal. So it’s basically a sliding scale of sorts.
Hope that explains it!
That did help, thanks for taking the time. I think I was thinking about mass and gravity not orbits. Again, I'm an idiot, so that's probably why I missed the central point of the cartoon. 😁