If I chuck a baseball out of an airplane I don't have to worry about accelerating the baseball to the airplane's speed, as I am also traveling at that speed.

Similarly, if a satellite is light enough in low-G to grab and manipulate from a craft that has straddled up along side it, would a single astronaut have enough strength to use his arms to put a satellite on a path that is effectively out of the way? Or could they just chuck it back at the earth so it can burn up on reentry?

> If I chuck a baseball out of an airplane I don't have to worry about accelerating the baseball to the airplane's speed, as I am also traveling at that speed.

But the speed of the baseball you just thrown out will be (ignoring air friction) that of the airplane +/- 40 m/s, assuming you're some super strong thrower.

> if a satellite is light enough in low-G

Microgravity doesn't mean the satellite is light now. It still has the same mass, it's just that you're both in free fall, so it doesn't pull away from you. For the purpose of throwing it, the satellite is just as hard to throw as it would be on the surface of Earth.

But even assuming it weighs as much as a fastball, when you throw it super hard, you'll change its velocity by... 40 m/s at best. Compare that with the orbital speed, which is many kilometers per second (e.g. about 7.6 km/s if you're on ISS). So e.g. instead of going 7.6 km/s, the thrown satellite now goes... 7.56 km/s. Which translates to one end of the orbit dropping by a couple hundred meters. So instead of 408km, it'll now go as low as... 407.5km, or something in that ballpark.

That's the limit of what you can achieve by just tossing things with muscle power.

edit: it's 24k, not 32k, I had the wrong number initially

edit2: actually now I'm not so sure, I might have had the right number initially. It's either 24k or 32k. Either way it's impractical.

24,000m/s is the difference in speed that the astronaut is already traveling with the speed necessary to get to the sun

Getting to the sun is really hard.

Chucking it back into the atmosphere is much easier, but GP was asking about throwing things into the sun.

I think the goal would be to first accelerate the astronaut to that level of velocity and then relatively adjusting its trajectory isn't so difficult. But, that is just my understanding that speed is relative (especially in space with no drag)

Speed is also extremely expensive due to the rocket equation- changing your velocity, that is.

It would surely be easier to accelerate space trash into the sun than it would be to accelerate both the astronaut and space trash into the sun.

I don't think we should do either of those, but less mass is always easier to speed up.