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Comment Re:Energy Conservation (Score 1) 557

Phase change drywall. Like this stuff, called "ThermalCore" from National Gypsum:

I don't know why it hasn't been commercialized yet (they've been stewing on it for years, and some places in Europe already have it), but it sure seems like a good way to make use of the latent heat of wax.

Comment Re:Mis-use=reviewer don't do their job (Score 1) 208

They're not crazy. This fantastic article from Nature in February 2014 shows how seemingly statistically certain events (e.g., p less than 0.01) can be thrown off by low probability events.


Frankly, I've always been a bit confused by the p value. It just seems more straightforward to provide your 95% confidence interval limits.

Comment Re:Oh...they have access to better imagery... (Score 1) 82

So, TFA states that the currently existing hardware in orbit has resolution of 46 or 41 cm, depending on which bird you're talking about. I'd really be shocked if I could tell the difference between 50cm resolution and 41cm resolution. Even future hardware, with a resolution of 31 cm, doesn't sound all that much better.

As others have opined, I don't see what benefit this will have, really. I can already see the small bushes in my backyard that I planted. I just see the size of Google's image database increasing by (50/31)^2 or about 2.6 times. Unlike the NRO and other government-based entities, I don't need to read license plates from space ... seeing roads and houses is good enough.

Oh, and nobody will ever need more than 640kB of memory. :)

Comment Re:What could possibly go wrong? (Score 1) 358

Agreed; there is no impact on safety. On one hand, I'm glad we won't be paying their over bloated, $277/hour pay rates. Yes, folks, regardless of who is doing the work or what they are doing, the commercial entities are required to reimburse the NRC at a rate of $277 per hour.
On the other hand, it's all for naught as they will likely be back-paid for their free vacation. That, and a variety of improvements and life extensions will get strung out even longer. Alas.

Comment Re:One hand, 12 o'clock ... (Score 4, Informative) 756

I was in an airbag-deploying accident about a year ago, and ended up with some pretty good bruises / rashes on my arms. I think I was at 10 and 2, roughly.

In the "ideal" case where you hit something and your hands remain at the 9 and 3 positions, this would be great. But I'm willing to wager that for most accidents, there is at least 0.2 seconds of [unprintable], in which case you will try to swerve out of the way. In this case, as was the case for me, your hands and arms will inevitably be right in front of the airbag, since you're twisting the wheel in an effort to go around whatever it is in front of you. The airbag goes off and your arms get pinned between the airbag and your chest ... or worse.

So, I applaud the intent to keep your arms and hands out of the way with the 9 and 3 o'clock positions, but I just don't think it will do any good in most real-world situations.

Comment Re:Good luck (Score 1) 148

I call BS.

To the uninitiated, I agree it sounds bad. "OMGWTFBBQ we're putting NUKES in SPACE!!1!"

But it's not actually that bad. The fact is, uranium is not that radioactive before it has been in a nuclear reactor. I have held kilogram-quantities of uranium in my hands -- and still have all 10 fingers to show for it. Plutonium is more radioactive -- half a kilogram is warm to the touch -- but it's not deadly as long as it stays external to your system.

The nastiness starts coming in after the reactor goes critical and fission products have a chance to build up. But you'd only let the reactor go critical AFTER the thing has left LEO.

Having designed a space reactor before, I know that it's quite possible to even to criticality measurements on the reactor (i.e., zero power measurements) before you launch it and still call the reactor "clean."

For some real fun-and-games, check out the re-entry of the Soviet TOPAZ reactor (Cosmos-954) over Northern Canada in the late 1970's.

Comment Re:why isn't thorium being developed? (Score 5, Informative) 299

Thorium isn't being developed in the US for 2 reasons:

1. Current uranium-based reactors are more affordable than thorium reactors.

2. The path for licensing a thorium-based reactor in the US is exceedingly uncertain.

While a thorium-based fuel cycle may be a good idea, it's just not going to be done by any commercial enterprise today. The costs and risks are too high. When staring at a $5B initial investment cost, any electrical utility is going to favor the known route ... which, frankly, could just as easily mean building 10 natural-gas fired plants instead of 1 big nuke.

India, however, is going full-bore on a thorium-based fuel cycle, and has already built a few reactors that are capable of accepting thorium. Copied shamelessly from

India's plans for thorium cycle

With huge resources of easily-accessible thorium and relatively little uranium, India has made utilization of thorium for large-scale energy production a major goal in its nuclear power programme, utilising a three-stage concept:

Pressurised heavy water reactors (PHWRs) fuelled by natural uranium, plus light water reactors, producing plutonium.

Fast breeder reactors (FBRs) using plutonium-based fuel to breed U-233 from thorium. The blanket around the core will have uranium as well as thorium, so that further plutonium (particularly Pu-239) is produced as well as the U-233. Advanced heavy water reactors (AHWRs) burn the U-233 and this plutonium with thorium, getting about 75% of their power from the thorium. The used fuel will then be reprocessed to recover fissile materials for recycling.

This Indian programme has moved from aiming to be sustained simply with thorium to one 'driven' with the addition of further fissile plutonium from the FBR fleet, to give greater efficiency. In 2009, despite the relaxation of trade restrictions on uranium, India reaffirmed its intention to proceed with developing the thorium cycle.

A 500 MWe prototype FBR under construction in Kalpakkam is designed to produce plutonium to enable AHWRs to breed U-233 from thorium. India is focusing and prioritizing the construction and commissioning of its sodium-cooled fast reactor fleet in which it will breed the required plutonium. This will take another 15 â" 20 years and so it will still be some time before India is using thorium energy to a significant extent.

All power corrupts, but we need electricity.