Realistic fusion drive with Epstein Drive-like performance | Hacker News Reader

Realistic fusion drive with Epstein Drive-like performance

toughsf.blogspot.com

50 pointslachlan-sneff37 comments

Everyone who has not watched The Expanse yet: start doing it. It is easily the best SciFi show in the last decade and a top contender for best SciFi show ever.

It has a slow start but is increasing pace and when you realize you are being watching seasons you are doomed because soon the year long wait starts :)

The books are really good, too.

I need to watch the series at some point.

They work nicely together.

I not sure how many realize this, but the books were actually written by a team of writers, well 2 writers, in parallel, defining the world, characters, and storylines. James S.A. Corey is the pen name of authors Daniel Abraham and Ty Franck. Great series too :)

And it get really interesting who their friends are down there in New Mexico :)

I read them. All of it including Novellas and stuff. They are awesome. Especially once you are used to the chapter by character thing GoT also does. But surprise, New Mexico connection :)

New season premieres Dec 14th! Already got a few friends hooked on it.

Dec 13th !!!

It's basically Game of Thrones in space, for whatever that's worth. I didn't like Game of Thrones because of the fantasy setting, but I'm loving The Expanse.

I half jokingly expected GoT to end with the Colonial Service starship arriving to figure out why Valiria lost contact a couple centuries prior and how to fix the mess the colonists put themselves into.

All the seasons are available free with Amazon Prime, fwiw.

take a fictional propulsion technology from [Sci-Fi TV show, movie or book] and apply the appropriate science to explain its features in a realistic manner

Doesn't everyone do that or is it just me? I always try my best to think of a way that such things could work.

That's how I watch magic and mentalism acts as well. Until now, I'd not considered such a similarity between Darren Brown and Geordi La Forge.

With the caveat that magic and mentalism don't actually work, but only appear to work. So a better analogy might be between magic/mentalism and those fake perpetual motion machines which appear to work but don't.

Is it fair to call the Rocinante a time machine? If it can achieve 5% of C in 37 hours it can go seriously relativistic in a reasonable amount of time. It becomes possible to travel across hundreds or thousands of Earth years in a lifetime, like Andrew and Valentine Wiggin or Colonel George Taylor.

The travelling through space feature is pretty cool too though.

If you want to go relativistic, you'll have to deal with the fact vacuum is not as perfect as you'd like it to be. You'll need some form of abrasion shield because you'll be hitting a thin wall of hydrogen at relativistic speeds.

Maybe with efficient fusion you could just push a small asteroid on acceleration, then drop it and use the drive plume as a shield on deceleration.

Question: Doesn't this already happen to us all the time every day? Isn't it the essence of all radiation damage to our bodies?

Atmospheric hydrogen hits you at around 10^3 m/s. Relativistic hydrogen hits you at around 10^8 m/s and has more mass, up to infinity.

Check https://en.wikipedia.org/wiki/Oh-My-God_particle for an idea of what being hit by relativistic particles will look like.

Bussard ramjet:

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

If the field manages to catch everything in the ship's path, that's good, but not all particles will cooperate. You'll catch some, push others out of the way and still get hammered by all the stubborn neutrally charged ones.

And that's only for the atomic scale. Smashing into a grain of dust at a relativistic speed is very destructive.

They really did sell everything at Radio Shack back in the day.

It's gratifying seeing a discussion that focuses on the central problem of waste heat control.

An "engineering challenges with today's technology" section would be great addition to this piece, I'm sure there'll be a few "biophysically possible but we don't know how" parts ;)

Would the heat absorbed by the heat shield be enough to power the igniter and the magnetic field?

Worst case scenario would be to use the heat to power a thermal rocket. Not an efficient use of propellant, but still doable.

Assuming 100% combustion of fuel is not realistic, especially with fusion.

If the engine manages to get half as much useful thrust out of the fuel, it's still a nice 1g all the way to your destination. Still quite a revolution.

How much would be realistic?

Maybe 2%? That’s based on yields common in nuclear weapons of this complexity. Fusion should be even harder to contain above critical temperatures.

Well... I guess even .04 G can be useful... And if we are only fusing 2%, we can bring the reaction to much closer to the ship itself.

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