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#11 Is it hype? or a possible real answer?

Posted: Tue, 19 Apr 16, 23:14 pm
by Commander
Okay, I know. When dealing with NASA nowadays this question could be asked about almost any endeavor they undertake. However this article has way to many buzzwords in just the title alone. The article is called NASA Works to Improve Solar Electric Propulsion for Deep Space Exploration. So let's see, there's: Solar; Electric; Deep Space; and Exploration. So out of an eleven word title, nearly half are buzzwords.

As many projects in the NASA welfare programs, this one is a big budget ($67 million) with a payoff in the "not that far off" future.

The problem with this solar powered ion propulsion system concept, especially for deep space missions, is that like all solar powered machines, if you run out of light, you have no energy. I'm straining my grey matter trying to remeber all the pertinent information, and this would probably be better left to Luke, but I'll stick my neck out.

Ion engines are not like those in fiction (Star Wars T.I.E. fighters, or Twin Ion Engine Fighters for example). While great speeds are possible, they do not have great acceleration. The other problem is the solar component. the further from the star, the less light is received and able to be used. So if you're in deep space, you're not getting great amounts of power.

http://www.nasa.gov/press-release/nasa- ... xploration

#12 Re: Is it hype? or a possible real answer?

Posted: Thu, 21 Apr 16, 19:39 pm
by Commander
That's my mistake, not NASA's. Thank's for the correction Joe

#13 Re: Is it hype? or a possible real answer?

Posted: Thu, 21 Apr 16, 23:39 pm
by Joe Wooten
Commander wrote:That's my mistake, not NASA's. Thank's for the correction Joe
Then I humbly apologize for calling you a A dumbass...... :D :oops:

#14 Re: Is it hype? or a possible real answer?

Posted: Fri, 22 Apr 16, 01:36 am
by luke strawwalker
13 kilowatts= about 17 horsepower (1kw=1.34 horsepower) Saturn V= 150 MILLION horsepower. SO, I think they've got a long way to go.

It doesn't really add up. Lots of folks have riding lawnmowers with bigger engines than 17 horsepower. Now, imagine trying to accelerate something the mass of a fully loaded 18 wheeler (or larger) to Mach 30 or more with a lawnmower motor...

That's the best comparison I can give.

Later! OL J R :)

#15 Re: Is it hype? or a possible real answer?

Posted: Fri, 22 Apr 16, 01:48 am
by bernomatic
True, all analogies are suspect and will crumble at some point, but if that lawn mower had no friction to overcome yet had plenty of traction to keep propelling it... it's akin to the man pulling the truck, train, cruise ship, whatever, with a rope in his mouth. Once he overcomes the initial inertia (of the object at rest), that inertia becomes the object in motion which must then be overcome to put the object back at rest. In space, there is going to be a lot less to overcome.
The main problem then becomes keeping the lawn mower supplied with fuel.

#16 Re: Is it hype? or a possible real answer?

Posted: Fri, 22 Apr 16, 23:53 pm
by luke strawwalker
"Give me a lever long enough and I'll move the world"...

Yes, it's POSSIBLE. BUT, is it PRACTICAL?? Methinks not.

Get the thrust up to about 100,000 lbs and then we'll talk again. Ounces or a few pounds of thrust ain't gonna cut it because of the delta-t problem (takes too long to accelerate, lengthening the mission unacceptably).

Later! OL J R :)

#17 Re: Is it hype? or a possible real answer?

Posted: Sat, 23 Apr 16, 11:25 am
by Joe Wooten
As you said earlier, it has all the buzzwords that the current administration loves to hear, so Bolton will approve it. The only thing they left out was some sort of sop to muzzies from those esteemed centers of space science in the middle east.