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Comment by sq_ | Hacker News Reader

> Can you aerobrake around a star?

Not a physicist, but it seems like you should be able to do something similar to aerobraking (not one-to-one since the Sun's "atmosphere" is different from a planet's). Maybe using a solar sail of some sort directed at the right angle?

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I went on a wiki-binge on this topic a few days ago and so I recognize this as a magsail[0]. It would be an attractive addition to an interstellar craft since it obviates the need to carry propellant for deceleration.

[0] https://en.wikipedia.org/wiki/Magnetic_sail

That's really cool. Definitely helpful in order to drop deceleration fuel requirements if we ever manage to put together a relativistic interstellar spacecraft.

In a bit over 1M years another star is expected to pass around 1000 AU from the sun. Chemical rockets should be able to get there in a decade or two. It's a huge stretch, but we have a million years to prepare.

Oh wow. Had never heard about that. Wouldn't that pass within the range of the Oort Cloud? Seems like we might have some issues from the gravitational effects if so (although that's assuming humans manage to keep ourselves going for another million years).

Something makes me doubt that humans will still be around at that time.

With the way we’re going, maybe not. But maybe we’ll shape up and some version of humanity will make it.

Gilese 710?

https://en.wikipedia.org/wiki/Gliese_710

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