Tag

science

Browsing

Wired on how space particles are helping map the inside of Fukushima Daiichi nuclear power plant:

The detector works like this: Durham and his co-investigators sandwich the pipe in question between two four-by-four-foot aluminum slabs. When an errant muon passes through one of the slabs, it sends a message to a computer, which logs the particle’s trajectory. The muon continues through the pipe, then passes through the slab on the other side—which again measures the particle’s angle. By calculating the difference between angles, researchers can get an idea of the path the muon took through the pipe’s molecules. And with enough muons, they can draw a pretty good picture of what’s going on inside the pipe.

Or inside anything, really. Muon detectors were invented after the 9/11 attacks, as a way of looking for smuggled nukes. It’s no problem to sneak a bomb past an X-ray detector. But muons can see through cars, can see through boats, can see through shipping containers. “At Freeport, in the Bahamas, they have a detector big enough to drive an 18-wheeler through,” says Durham. The detector can find a lump of uranium in about a minute. “A lot of stuff goes through the Bahamas on its way to the East coast,” says Durham.

But finding a glowing hunk of uranium is a lot easier than detecting the structure of a faulty pipe—hence the Los Alamos breakthrough. Compared to the Bahaman detector, the Los Alamos model moves pretty slow. This is because muons are rare. “We only get one muon per square centimeter per minute,” says Durham, so it can take about 4 to 6 hours to survey a single section of pipe. Increase the area of the detector, and you can get a faster picture.

This sounds quite bad ass!

The Los Angeles Times on Jupiter and Venus meeting in the summer sky tonight and how they will be visible to the naked eye:

Amateur astronomers will be pulling out their telescopes, but you don’t need any fancy equipment to view it. Just look to the west: The two planets will be so bright in the sky that you should be able to see them with the naked eye even during the fading twilight glow.

From our vantage point on Earth, the two planets will be just one-third of a degree apart — which is less than the diameter of the full moon, according to NASA. Jupiter can be seen just above the gleaming spot that is Venus. They also will appear to be roughly the same size.

Both are illusions, of course: Venus is our nearest neighbor, sitting closer to the sun, and Jupiter sits far out in the solar system, at roughly five times the distance from the sun to the Earth. Because the one-eyed gas giant is so far away, it appears smaller — which is why it can look comparable to Venus, which is roughly the size of Earth.

Too bad Tokyo is covered with rain clouds tonight otherwise I would really want to get a good look at both.