this post was submitted on 06 Jan 2025
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Okay im curious. What about shooting something into the sun is very hard?
The earth has a lot of angular momentum, in fact the planets combined have more than the sun and planet formation may actually be necessary to "bleed off" angular momentum from protostellar discs for star formation, but I digress. So if you were to aim directly at the sun you'd miss it wildly as the tangential motion of the earth would be added to your motion. Even worse it would miss the sun, go around it, and orbit back to where you came from. A bad thing if you were trying to toss, say, radioactive waste into the sun. To hit the sun you have to bleed off all of that angular momentum by using rockets (very expensive) or do what NASA usually does and use gravity assists swinging by planets to gain or lose energy. The Parker solar probe had to do a bunch of swings past Venus to lose enough angular momentum to get close to the sun.
I was assuming rockets were an option like going to the moon. Cost wasnt something i thought we were factoring in thats not really a factor in just trying to send a space ship at the sun and having it get there. It doesnt have to be moving fast (relatively) to get there so you just need good aim and to keep it on track.
Cost should be its own problem separate from the objective. Assume 0 costs, how hard would it be?
It requires a LOT of energy to counter the earth's orbital motion. Hitting the moon is different because the moon is traveling with the earth and you are going outwards. Energy is always part of the equation since orbital mechanics is all about energy. You can't ignore it by saying "Assume 0 costs, how hard would it be?" then we could just say it can approach the speed of light since we are ignoring any energy costs.
"It doesnt have to be moving fast"
But you will be moving fast, you are starting at an angular speed of 30km/s. The Apollo missions with their massive engines reached 11 km/s. Now think of someone wanting to dump hundreds of tons of nuclear waste into the sun and the energy that would require.
Maybe this explains it better:
https://www.youtube.com/watch?v=LHvR1fRTW8g