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2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math

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>> No.3386109

It's great, but it's currently incapable of providing much thrust. I wouldn't rely on them without some kind of high impulse backup.

>> No.3386111

bump

>> No.3386118

So are those "39 days" claims bunk?

>> No.3386121

So... Lightsabers?

>> No.3386130

>>3386118
with the existing rockets, very much so. They only give a few pounds of thrust, so a mission in under about 4 months wouldn't be possible.

>> No.3386148

> VASIMR

>> No.3386158

here is the physorg article:

http://www.physorg.com/news/2011-07-zubrin-vasimr-hoax.html

>> No.3386172

I don't like that guy's attitude he seems to dislike anything new a radical. And VASIMIR limited capabilities has been known through out the spaceflight communities for sometime now.

>> No.3386188

>>3386158
That's bullshit. the VASIMR isn't supposed to be a powerful engine, it's supposed to provide constant thrust to allow speed to gradually increase or decrease. You can't make a far comparison between chemical and electrical engines like that.

>> No.3386196

Why is he comparing the proposal with the energy density of an old soviet reactor lol? Its like comparing Gen III/IV powerplant with RBMK power plants from the 50s.

Its about energy density. The "39 days" VASIMR trip requires 1 kW / kg energy density of the reactor to be feasible. Current designs of space reactors like SAFE-400 have cca 0.1 kW / kg, but there is much room for improvement. I wouldnt say its completely unfeasible. Even twice that time would still be better than current 6 months transit time with chemical rockets.

Even if it would not be feasible for Mars trip, anywhere beyond Mars orbit the VASIMR + nuclear reactors clearly wins.

>> No.3386225

>>3386172

>I don't like that guy's attitude he seems to dislike anything new a radical.

Yeah thats also my observation. His whole "Mars Direct" proposal is just another "plant a flag, scratch a planet and go home", instead of feasible way of the colonisation of Mars. Seems like he only wants to see humans on Mars before he passes away..

There is no point of colonising Mars until we colonise the LEO and Moon, either way. At least not if some new gamechanger like "39 days" thruster is developed, which he seems to be arguing against...

>> No.3386385

Hes also against funding for fuel depots saying something along the lines of an interplanetary reusable non atmospheric spacecraft or infrastructure ala Nautilus X or Bigelow is not necessary.

>> No.3386420

>>3386385
FGS, FDS

We don't even have anything reusable and manned any more. No idea how he thinks that would work.

>> No.3386481

>>3386106

Well, it was not really 39 days, but in actuality over 100 days. That thing needs to accelerate for tens of days to reach full speed.

The trip will still be awfully long.

>> No.3386521

Guys, the velocity in space is not about the power of the engine. The only things that count is the velocity of the exhaust and the mass lost in the process.

That is why plasma reactors (like VASMIR) are far better than chemical propellant.

The only thing that chemical propellant are useful is for takeoff and attitude control.

>> No.3386651

>>3386521

Everybody knows that. But that's not what where talking about.