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by DarmokJalad1701 11 days ago
> so it's not too different to "get there" and "orbit there".

But to "get there" within any reasonable timespan requires going really fast - which is currently highly impractical. And then once you get there, you have to them cancel pretty much all of that velocity which is not just a "few percent more delta V".
1 comments
hparadiz 11 days ago
We can do 7-8 AU per year right now using tech we have. Voy 1 and Voy 2 are moving at 3.59 and 3.25. A starship sized rocket could also possibly get a small payload that separates to 15 AU. This is all using conventual propellent. If you consider using nuclear explosive as a prepulsion technique the math starts to change substantially and you can achieve even 25 AU / year.

https://ntrs.nasa.gov/api/citations/20140013260/downloads/20...

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DarmokJalad1701 10 days ago
Sure. But then how do you go from 7-8 AU/yr (33-38 km/s) to whatever the orbital speed is at that distance and also point that velocity vector in the correct direction for the orbit?
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cyberax 10 days ago
Technically, you don't need to stop. Gravitational lensing does not work like regular lenses, there is no "focal distance".

You have to be so far because that's the minimal distance where the Einstein ring becomes larger than the Sun's apparent diameter.

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