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Comment Re:Meh, I'll wait for confirmation (Score 2) 412

The news reports are saying it was between a magnitude 4.8 and 5.1 on the M scale (kinda like the Richter scale).

This is remarkably similar to the 2013 test, which was also magnitude 5.1. The USGS has a nice summary plot of the 3 previous tests. All else being equal (namely, the coupling between the test tunnel and the surrounding rock), it looks like this test was about as big of a "pop" as the 2013 test.

Comment Re:earth helium (Score 1) 267

Going to the moon is a really dumb way to get your He3.

A far easier way is to use a Tritium Producing Burnable Absorber Rod. (pdf link) Rather than putting UO2 in the fuel pellet, put lithium aluminate (LiAlO2) in there.

This has been going on at the Watts Bar Unit 1 nuclear power station since 2004. Sure, more tritium has leaked into the coolant than expected, but tritium is a pretty benign radioactivity source.

Harvest the tritium, which decays into He-3. Voila. Far easier than going to the moon. Sheesh.

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. http://www.nrc.gov/reading-rm/doc-collections/news/2013/13-012.pdf
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.

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