It’s a natural formation that contained a critical mass of uranium.

Now that is pretty damned cool.

Via SayUncle

John Holdren told The Associated Press in his first interview since being confirmed last month that the idea of geoengineering the climate is being discussed. One such extreme option includes shooting pollution particles into the upper atmosphere to reflect the sun’s rays.

Brought to you by the government that has been so successful at managing the economy, it’s budget, the “war” on drugs, etc.

The weather, like the economy, is a chaotic system and inherently unmanageable. Attempts to actively manage chaotic systems ALWAYS fail, usually disastrously (See USSR, Mississippi RIver flood control).

And the Obama fail train keeps on rolling.

It turns out that if you peel the popular adhesive tape off its roll in a vacuum chamber, it emits X-rays. The researchers even made an X-ray image of one of their fingers.

It has to be in a vacuum, but still…    

Totally cool, and it’s not April 1st, so it might even be true.

“Last week, three prominent neurosurgeons told the CNN interviewer Larry King that they did not hold cellphones next to their ears.”

Well the first problem is it’s Larry King. The second problem it’s neurosurgeons, a medical specialty prone to knowitallitis.

When you’re talking about damage to humans, there are two kinds of Electromagnetic Radiation: Non-Ionizing and Ionizing. The Ionizing type is pretty much everything with a wavelength smaller than the color purple. Ultraviolet, what causes sunburn, is ionizing electromagnetic radiation from the Sun. (Although you can also get UV from a sunlamp, it’s what makes a tanning bed work.) X-rays and gamma rays are also forms of ionizing radiation. It’s called ionizing radiation because the wavelength is so small it can knock electrons off atoms causing damage to the molecules that are part of your body. If you receive enough ionizing radiation the cellular damage can be fatal.

Fortunately for us, the chunk of the EM spectrum that cell phones operate in is the non-ionizing part. Non-ionizing EM radiation can also hurt you, but it does it by directly transferring energy, also known as heat.

Any radio wavelength can burn you if there’s enough power behind it. That’s how a microwave oven works. The magnetron in a microwave oven puts out 700 to 1500 Watts and the heat cooks the food. But that effect is nothing special to microwaves. ANY RF with that kind of power behind it will burn you. Try touching a 60 Watt light bulb while it’s on sometime. Oops, that hurt didn’t it?

That’s the claim about cell phones, that the RF from the phone heats your head and causes long term damage.

And it’s total bullshit.

The average adult human emits 95 Watts in infrared (the part between microwaves and visible light) all day long. A GSM cell phone emits, at most, two watts.

If the fraction of a degree of heating from a cell phone caused damage, how much damage must be caused by touching another human, something 47 times hotter than your cell phone? (I’m not talking about the heat from the battery, that’s much hotter as you know if you’ve ever had cell phone ear from a long conversation.) If heating from cell phone radio waves could cause damage then even standing next to another person would be deadly.

That 100 Watt light bulb in the bedside table lamp would be killing you.

Even worse, the Sun’s energy is about 1000 Watts per square meter at the Earth’s surface, (Give or take depending on latitude and elevation.) If the heat from a cell phone was dangerous, the Sun would be KILLING you.

Clearly we’re not all dead.

Feel free to hold your cell phone next to your head. It isn’t dangerous at all, unless you’re driving or next to me in a movie theater.

In the last couple of decades tritium has been used for self illuminating watches and gun sights. I’ve also seen some key chains and exit signs that use tritium. The decay product of tritium is the beta particle which is pretty much the same thing that makes the picture tube in your old TV work. The nice thing about the beta particles emitted from tritium is they won’t go through skin so unless you eat it, or breathe it, tritium is safe. There are chemicals we use every day that will kill you a lot quicker than tritium if you ingest them.

In the photo below are a couple of watches with tritium inserts. The one on the left is about two years old. The one on the right is eight years old. You can see that the older one has faded a bit, but it’s still bright enough to see in the dark. Tritium has a half life of about 12 years, which is why the seven year old watch isn’t as bright as the two year old one. The two year old watch gives off enough light to read a book if you hold it close enough to the page (and you let your eyes adjust to the dark).

(the pictures are all 15 second exposures in a dark room)

Below are the TFOs on my XD .40. The rear sight has two yellow dots and the front is green. It’s a little fuzzy because my camera doesn’t have manual focus.

Here are the Trijicon sights on my new XD Sub Compact. They’re green on the front and back. I like the green front sight, but I like the idea of a less bright rear sight because I think it naturally draws the focus to the front sight. I say idea, because I haven’t spent much time shooting either in low light. For some reason ranges don’t like people shooting in the dark.

The point of all this is that there is a place for products that use radioactive decay for power. It’s time to get over the fear of radioactivity and realize that properly used, radioactive materials are safe and useful.

Besides, it’s cool to have nuclear powered stuff.

What are the real possibilities for the current 700 MHz auction and the 12MHz that AT&T recently bought?

In the previous 700 MHz auction none of the winners did anything with the spectrum space. To the auction winners it was just an investment that they never intended to use. Last year AT&T purchased 12 MHz of 700 MHz space from previous auction winner Aloha Spectrum Holdings and the FCC approved the purchase last week. (A few years ago I talked to Aloha about leasing some of the space for the company I worked for at the time. I was told by Aloha that they had no intention of doing anything with the space, they were just holding on to it as an investment.)

There are several things AT&T can do with it’s shiny new 700 MHz space.

They can sit on it.

• The investment theory: Spectrum is a somewhat limited resource, and while new technology allows you to do more with less all the time, the Shannon Limit is a hard cap on the amount of data you can shove through a given amount of bandwidth. Market forces, allowed to work, will guarantee an increase in price.

• The anti-competitive theory: They bought it to keep someone else from using it. AT&T has a huge investment in an existing cellular network. Spending $2.5 billion to protect the revenue stream of that network would make perfect sense.

They can add it to the existing cell network.

• And use it for a data service. Since 700 MHz has “better” propagation characteristics than existing cell frequencies AT&T wouldn’t have to add 700 MHz equipment to all of the existing cell towers. If someone will make the necessary equipment it could be a relatively inexpensive way to layer a data service onto their existing cell network and not have to rob voice channels for 3G data service.

• And use it for voice service. Coverage for cell networks is always a problem. AT&T could use the “better” propagation characteristics of 700 MHz to enhance the coverage of existing cellular voice service.

They can create a new service.

They can add it to what they win in the current 700 MHz auction for any of the above uses.

(The reason better is in quotes above is that propagation is a double edged sword. Yes, 700MHz goes through trees and houses very well. The problem is it goes through trees and houses very well. Current wireless broadband technologies rely on trees and houses to attenuate the RF signal to reduce interference between different towers. Take away that attenuation effect and you have to spread out your towers, reducing aggregate available bandwidth.)

In the GSM PCS band (1800MHz – 2000MHz), the C,D,E and F blocks are all 10 MHz, and 12 MHz of the 700MHz band could be used similarly. So the voice application would work.

EDGE uses the same channels as GSM either in the PCS band or the Cellular band (800MHz – 900MHz) but there is only one EDGE user per channel instead of 8 voice users per channel. (That’s one reason why cell carriers hate VoIP.) So you could theoretically use 700MHz for EDGE.

HSDPA builds on GSM channelization but can combine channels and codes to achieve a theoretical maximum throughput of 14.4 Mbps. Typically you could expect 1 to 3 Mbps down and a maximum of 384Mbps up. Unfortunately HSDPA is a channel pig and I don’t think AT&T deploys HSDPA where they only have block C – F PCS licenses. (Someone please correct me if I’m wrong about this. I’ve looked at AT&Ts licensing in the FCC database and compared it to acknowledged HSDPA deployments. It looks like they’re only deploying HSDPA where they have licenses in the A and B blocks of the Cellular (25MHz) and PCS (30MHz) bands. As usual though, I’m quite prepared to be wrong.)

I think it’s unlikely that AT&T will use it’s 700MHz space for HSDPA, unless it can pair it with one of the 700MHz blocks currently being auctioned. Either the A or B blocks, both 12 MHz, could be combined with the 12MHz from Aloha to make 24 MHz available, comparable to AT&T’s existing A & B blocks in 800MHZ and 1900MHz. If AT&T wins one of those blocks it would be reasonable expect AT&T to add 700MHz to their existing GSM system.

What about non-cellular uses of 700 MHz?

WiFi and WiMax both use a 20 MHz channel. In the 2.4 ISM band there’s enough room for three non-overlapping WiFi channels. WiMAX is used on licensed frequencies, currently 2.5 GHz in the US. AT&T’s 12MHz isn’t wide enough to use even one WiFi or WiMax channel, and even paired with something from the current auction they’d only have one channel. You can’t deploy a wide area broadband service on one channel. You can forget nationwide WiFi. There’s not even enough bandwidth available to act as back haul to traditional WiFi access points. This Wikipedia article on Spectral Efficiency has a great table comparing the available data throughput rates for different technologies.

So the most likely use for AT&T’s (Or anyone else’s) 700MHz spectrum would be to augment the existing cellular system. That doesn’t get us the high speed data nirvana some people seem to be expecting.

On the other hand, more 3G data with better coverage isn’t bad, especially if the Google influenced open access rules survive.

Let’s try to be a little more realistic in our expectations, OK?

The TFOs are MUCH better than the factory sights. That green front sight draws your eye like a magnet. It’s hard to NOT look at it. They show up good in the dark too. The tritium gives it just enough glow to see without being too bright. (Nuclear powered sights… Makes my inner geek squeal with happy.) I need to find a fiber optic front sight for my Para-Ordinance .45 now.

The gunsmith said he wound up having to use a steel punch and a big hammer to get the factory sights out. They were pretty mangled, but I was going to throw them away anyway. So if you have an XD and you want to replace the factory sights, don’t even bother trying it yourself, unless you’re a competent gunsmith and in that case why are you listening to me?

UPDATE: Trusty Sight Alignment Tool worked. Bore sight laser is now dead center on the front sight. Of course I’ll have to actually shoot it to make sure, but that’s the fun part.

And here’s the picture of XD with TFOs and the Trusty Sight Alignment Tool. You can see the front sight glowing even in the somewhat dim room light. It’s extremely bright in daylight.