this post doesn’t apply to me at all but here’s a paragraph about some third party bullshit that’s tangentially related at best, but really doesn’t meet the spirit of the post
Why is that - wouldn’t you be working against solar gravity? Like you don’t have to get them there quickly, just launch them in some orbit that will decay and be taken in?
The curvature of spacetime does wild shit to how you would expect physics to work. If you want to fall into a gravity well, you have to slow down or you’ll just slingshot past it.
Why would an orbit decay without something to slow the spacecraft down like an atmosphere? The problem is that any object we launch from earth has a lot of orbital velocity, which makes it almost impossible to hit the sun directly, you would have to use a lot of complex gravity assists from the inner planets to take away enough momentum. Using gravity assists to accelerate outwards is much easier
That’s what the premise of this post was. It’s a common saying to “shoot something into the sun”, which sounds easy at first but is actually quite hard to do. That’s the joke
My argument is it’s more energy efficient to shoot something towards the sun that will have the same result as hitting the sun than it is to get it out of the solar system.
Because the Earth is really cookin’, and anything anyone you hurl toward the sun will inherit that orbital velocity as well, meaning that they’ll actually end up going around the sun, instead of into it. And due to the speed it would pick up on its way in, it would basically take up a highly-eccentric yet stable elliptical orbit.
“Well, what if we throw them in the other direction, to make up for it?” That’s called retrograde, and that’s basically exactly what you’d have to do: cancel out the Earth’s entire orbital velocity. Which would take a lot of energy, plus a couple of really exacting gravity assists from planets on the way in.
(Edit to add: I may have explained this poorly. Basically, if you don’t change your orbital speed at all, any movement you make toward or away from the host body means you just end up in an orbit of the same average distance, but in a more eccentric [elliptical] shape.)
By contrast, even though the escape velocity from the solar system is no slouch (42 km/s), you get to start with the Earth’s orbital velocity (30 km/s)–meaning you’re already a little under 3/4 of the way there. Plus, if you can make it to Jupiter and Saturn, you can get a significant gravity assist, and they’re much bigger targets for such a maneuver than Mercury or Venus are.
So, yeah, bottom line: you only need a delta-V of about 12 km/s to get out of the solar system, but a delta-V of 30 km/s to get to the sun without going into orbit.
Good question, but if you cancel out only a little bit of orbital velocity, you just orbit in a little bit closer. Without any appreciable drag acting on you, there’s nothing that will keep your orbit decaying. You’ll just be in a smaller, perhaps slightly more eccentric orbit.
These are all technically correct but fairly inconsequential. Even just to graze the sun you need to lose 90% of your orbital velocity. And although everything orbiting the sun will eventually fall in, the friction is really low. It will take billions of years to lose enough velocity to fall in.
If you’re willing to settle for that kind of timeline, you could “launch someone into the sun” by just…leaving them on Earth for five billion years. At that point, the sun will become a red giant and probably expand to engulf the Earth.
What does engulfing the earth mean to you? The mass of the sun expanded to a body 1 au would not be very dense. My money says the earth would continue to orbit “inside the sun” for quite a while, but the orbit would degrade more quickly.
But yes, I argue get them out of the earths gravity well and let Newton handle the rest, no reason to propel them in any direction, eventually they’ll get to the sun.
So, yeah, bottom line: you only need a delta-V of about 12 km/s to get out of the solar system, but a delta-V of 30 km/s to get to the sun without going into orbit.
This is true, but the possibility of gravity assists mostly nullifies the difference. If you can get out to Jupiter you can basically choose: either let it sling you out of the system, or let it cancel out all your orbital velocity so you fall into the sun.
That’s the thing - in space, orbits don’t decay. Orbital decay only happens if there’s dust or atmosphere that you bump into along your orbit to slow you down. But in interplanetary space, there’s no dust or atmosphere, and certainly not enough to decay your orbit fast enough to achieve results (otherwise, the Earth would have already decayed and melted in the Sun)
You need to spend fuel to lower your orbit to hit the Sun, and you need to spend fuel to raise your orbit to escape the solar system. It turns out to be really freaking difficult to hit the sun because it simply requires so much fuel to lower your orbit enough to hit the Sun.
You are making 2 opposing assumptions there, 1) there is nothing to bump into in outer space, the earth picks up 43 tons of new mass every day.
the earths orbit would decay, the earth is absolutely massive compared to the amount of mass gained, and also off gasses a significant amount of mass every day.
If orbits don’t decay, why do even high orbit satellites need to make elevation corrections?
If you put a small body into outer space it would absolutely be (slowly) effected by the miasma of particles out there.
And let’s not forget we don’t have a time table for reaching the sun, and we aren’t aiming for the middle of the sun to see results. And as you approach the sun you will bump into more and more particles as they too are being drawn around the sun.
It’s an easy talking point from the Internet and high school text books, it is disregarding of many actualities of our universe. It would be true if the sun were an infinitely small point on a 2 dimensional plane with a perfect lack of friction.
And while for instantaneous results it would be easier to get something out of the sun’s gravity well rather than hit the exact middle of the sun, practically, if you have time, and you don’t actually need it to hit dead center of the sun, it’s much cheaper and easier to incinerate something proximal to the sun than it is too send it out of the solar system.
Also let’s not forget gravity sling shots work in both directions.
I live on a crappy golf course, our fees are $89 a month they don’t provide anything, we can’t have fences over 4ft the fence has to be see through, we can only choose certain colors to paint our houses we can’t store trash cans outside we got a notice for a single weed there is constantly people driving around taking pictures it freaking blows we are selling and the next place will have no HOA
Yeah, but propelling them out of the solar system just sounds like the kind of fake-ending that ends up with the super villain coming back stronger in a decade. Have we learnt nothing from science fiction? You have to destroy your foes whilst you can.
They can still come back from another parallel reality or some such - villains are like cats, they always come back (unless they are bored and then they don’t).
7: When I’ve captured my adversary and he says, “Look, before you kill me, will you at least tell me what this is all about?” I’ll say, “No.” and shoot him. No, on second thought I’ll shoot him then say “No.”
13: All slain enemies will be cremated, or at least have several rounds of ammunition emptied into them, not Left for Dead at the bottom of the cliff. The announcement of their deaths, as well as any accompanying celebration, will be deferred until after the aforementioned disposal.
Also, some people see abortion as a really big deal. The Vatican says they see abortion as an assassination, but also likes Harris allowing immigrants to come in.
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