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I'm not rocket scientist, but it seems like the author is calculating a decreasing spiral into the sun rather than an impact. Why not slingshot around a planet and barrel into the sun with all of the orbital velocity still intact.
Gravitational assists can help, but they can also help you get other places. Getting to the sun would still be ridiculously hard compared to the alternatives.
Its generally not worth it to give smart answers to dumb questions. I guess its a pet peeve of the author though.
Why is that so? It's not a particularly dumb question for many people that don't know anything about launch costs or the massive amount of energy. I'd bet many people think if you can get it out past the moon's orbit it should start to fall into the sun. And even if it was a flippant question, showing exactly how wrong it is through an in-depth analysis is a great way to refute such positions.
> I'd bet many people think if you can get it out past the moon's orbit it should start to fall into the sun.
This thought is actually true, to a first-order approximation. If you time it right and use gravity slingshot(s) to bleed off velocity and/or adjust the direction towards the sun. The amount of delta-V needed after the moon is basically noise compared to the amount needed just to leave the surface of the earth (which is HUGE, as the author points out).
It's still probably cost prohibitive, but the delta-V required is a lot less than the author thinks.
Jupiter would be just as good of a dump or we could just launch on an extra solar trajectory. Hell, we could just put it on a large, non-equatorial orbit around the Earth and it would be effectively gone with the added benefit of being able to recover it should we find a reason to. Space is a big enough place to dump an Earth's worth of trash.
The only problems are cost and the risk of explosion during launch.
I'm not rocket scientist, but it seems like the author is calculating a decreasing spiral into the sun rather than an impact. Why not slingshot around a planet and barrel into the sun with all of the orbital velocity still intact.
30km/sec is a LOT of velocity change, and you'd need to cancel practically all of it to actually fall into the Sun.
Way harder than getting to any of the planets.
(Assuming gravity assist is used)
I've been curious about his last paragraph for a while - send trash out into nowhere - and unless I'm being an idiot, it looks like we'd still be paying (at the author's implied Saturn-V costs) ~48 million USD per short ton of waste. Compare this to Yucca Mountain's current cost of $9b for ~77k short tons of storage (~$117k/sh tn) and it's still pretty awful. We do get the ongoing benefit of no upkeep and happy NIMBY…
Is there any way to use drag to decay the orbit? We don't have to reach the sun quickly . The solar wind is blowing past, is it possible to "sail" against that at an angle and - over time - dump orbital velocity and so end up in the sun?
To tie this back to solar sailing, there's obviously no fluid interface in space, so to the extent that solar sailing is possible, solar sailing "upwind" toward the sun is not.
I'm not rocket scientist, but it seems like the author is calculating a decreasing spiral into the sun rather than an impact. Why not slingshot around a planet and barrel into the sun with all of the orbital velocity still intact.
The ~30km/s figure is what you'd need to drop it straight into the sun, no spiraling involved. Gravitational assists can help, but they can also help you get other places. Getting to the sun would still be ridiculously hard compared to the alternatives.
1. http://www.wolframalpha.com/input/?i=orbital%20velocity%20of...