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f13.net General Forums => General Discussion => Topic started by: Venkman on December 20, 2008, 05:36:03 PM



Title: All you need is a tracking system...
Post by: Venkman on December 20, 2008, 05:36:03 PM
... and you could disintegrate someone from space.

(http://www.darniaq.com/Images/real-genius-laser.jpg)

Or, well, maybe just generate some power anyway (http://www.scribd.com/doc/8736849/Space-Solar-Power-SSP-A-Solution-for-Energy-Independence-Climate-Change)

Normally, I relegate lasers from space to Larry Niven novels. But this showed up on Change.gov (http://change.gov/open_government/entry/space_solar_power_ssp_a_solution_for_energy_independence_climate_change/), and is currently garnering much discussion (and was picked up by Slashdot too (http://science.slashdot.org/article.pl?sid=08%2F12%2F20%2F219209&from=rss)).

That this is actually getting serious consideration from our next President shows some serious geek cred. I like it.

Edit: wrong link was wrong


Title: Re: All you need is a tracking system...
Post by: Trippy on December 20, 2008, 05:37:57 PM
First link going to the wrong place.


Title: Re: All you need is a tracking system...
Post by: Venkman on December 20, 2008, 05:55:26 PM
I blame aliens. From space.


Title: Re: All you need is a tracking system...
Post by: Chenghiz on December 20, 2008, 06:37:16 PM
If they can get wireless power transmission to be viable at all, it pretty much solves tangled wires, electric power generation, and personal transportation problems all at once. I totally thought of it first, though.


Title: Re: All you need is a tracking system...
Post by: bhodi on December 20, 2008, 10:29:22 PM
This has been semi-viable for a long time. The limiting factor is, and always has been, cost per pound to throw something into space.


Title: Re: All you need is a tracking system...
Post by: apocrypha on December 21, 2008, 04:15:51 AM
To be fair the authors do acknowledge that:
Quote
Economics is the Key Barrier
. The extremely high cost of space transportation and building spacecraft is the principal barrier.  Some believe the cost of SSP is so high that it will never be economical for baseload power.  Never is a long time and we disagree.  More importantly, the NSSO disagrees.


However their "solutions" to this are, frankly, laughable:
Quote
The solution to the cost challenge is straightforward: 1) Achieve cheap & reliable access to space, 2) Apply high volume mass production assembly line techniques to spacecraft construction, 3) Reduce the technical risk with basic research and technology demonstrations, and 4) Adopt proven government approaches to incentivize private industry investment, development and operation.
 

1) and 4) in particular gave me a chuckle.


Title: Re: All you need is a tracking system...
Post by: Morat20 on December 21, 2008, 07:50:17 AM
1) and 4) in particular gave me a chuckle.
The space elevator people are quite serious, and closer than you'd think.

Guy I work with sat next to one of the engineers working the Space Elevator stuff, and spent most of a dinner listening to him talk. Apparently they're down to two major roadblocks -- first is the length of nano-tubes they can generate. They need to grow them in foot long lengths, and they're only up to 4 inches or so. (However, five years ago, they could only grow them in millimeter lengths). The second -- and to this guy's mind, the most problematic -- is that there's a time during construction in which the elevator ribbon is too fragile to handle a micro-meterorite strike, but big enough to make it really damn likely it'll get hit.

So there's about an 8 month period in construction where, at the moment, there's a high liklihood that the ribbon will take a strike, and it won't be big enough to hold together for the next crawler up (each crawler repairs the ribbon as it climbs). There's some stuff with power generation and transmission, and a lot of stuff about security, but they've only got the two major engineering hurdles.

Oddly enough, that's only a problem for the first elevator. After you build one, the others are easier -- you ship the complete ribbon up the first elevator and just lower it down to the base station.

In any case, it'd lower cost to LEO to somewhere between 10 and 100 bucks a pound.


Title: Re: All you need is a tracking system...
Post by: apocrypha on December 21, 2008, 10:51:29 AM
Jesus that sounds like something out of a sci-fi novel to me. I must be getting old ffs  :uhrr:

So why the nanotubes? Is that just because of the tensile strength or is it something to do with superconductivity?


Title: Re: All you need is a tracking system...
Post by: Lantyssa on December 21, 2008, 11:39:50 AM
Tensile strength combined with flexability and corrosion/oxidation resistance.


Title: Re: All you need is a tracking system...
Post by: Yoru on December 21, 2008, 02:53:34 PM
I remember doing some research on this several years ago for a paper while in university. Aside from the launch/lift problem, the other problem is the actual wireless power transmission. There's massive efficiency losses in converting EM radiation into electricity; the best you can do is microwaves, in the 80% range at the moment.

And with microwaves, you need to build a gigantic phased-array microwave antenna in space, on the order of kilometers on a side. We don't have the materials science necessary to build one large enough for serious usage that won't tear itself apart. And then you need a similarly-sized receiving antenna on the ground. Although I suppose we don't really need Utah anyway.

Still, it's a decent idea and we should be funding more basic and applied research at the federal level anyway.


Title: Re: All you need is a tracking system...
Post by: Venkman on December 21, 2008, 07:44:17 PM
1) and 4) in particular gave me a chuckle.
The space elevator people are quite serious, and closer than you'd think.

That reminded me of this (http://forums.f13.net/index.php?topic=12530.msg422811#msg422811) which then reminded me of this (http://www.eurekalert.org/pub_releases/2007-12/uoc--nbs120707.php).

This is one of those areas of sci-fi I actually think I'll see in my lifetime. Granted, I should have considered the Internet "the future", but since I doubt we'll have ftl travel nor particle transportation, I'm hanging my hopes on Space Elevators.

Tell your friend's engineering buddy to get crackin'!


Title: Re: All you need is a tracking system...
Post by: apocrypha on December 21, 2008, 11:31:54 PM
This is one of those areas of sci-fi I actually think I'll see in my lifetime. Granted, I should have considered the Internet "the future", but since I doubt we'll have ftl travel nor particle transportation, I'm hanging my hopes on Space Elevators.

It's nearly 2009. Where's my goddamned silver suit and flying car?!  :mob:


Title: Re: All you need is a tracking system...
Post by: Mrbloodworth on December 22, 2008, 10:03:28 AM
Hay, is this that one reactor type from sim city that would occasionally start slicing your city in half?  :drill:


Title: Re: All you need is a tracking system...
Post by: rattran on December 22, 2008, 12:02:07 PM
Meh, so we slice Utah in half occasionally. It's totally worth it.


Title: Re: All you need is a tracking system...
Post by: schild on December 22, 2008, 12:02:47 PM
Hay, is this that one reactor type from sim city that would occasionally start slicing your city in half?  :drill:

Eh? The Microwave power plant?


Title: Re: All you need is a tracking system...
Post by: Mrbloodworth on December 22, 2008, 01:17:48 PM
Hay, is this that one reactor type from sim city that would occasionally start slicing your city in half?  :drill:

Eh? The Microwave power plant?

The beam from space. yes.  :grin: