I love XKCD. How is it that a comic strip has such good technical explanations? Anyway, here you'll find a chart of the ionizing radiation dose a person can absorb from various sources. Check it out. You'll feel much smarter.
Students with the Department of Nuclear Science and Engineering at MIT have been keeping a really great blog about the ongoing struggle to cool and stabilize the nuclear power plants in Fukushima, Japan. It's my new go-to source for information.
Estimates of the amount of oil that spilled from the ruined Deepwater Horizon wellhead vary greatly, so it's tough to pin down a total amount. (The short answer is, "a LOT.") But that difficulty hasn't stopped a bunch of different sources from trying...
The official estimate is that some 50 million to 140 million gallons spilled.
Boston.com has a nice gallery of images to help visualize just how much oil has spilled in the Gulf of Mexico. (Unfortunately, the numbers and comparisons only reflect the amount spilled as of June 11, so it's a month out of date. But still fascinating.)
The Alaska Dispatch has a counter that estimates the total amount of oil spilled. (They figure some 92,240,117 gallons, or about 2,196,193 barrels, over 87 days.)
And, last, here's a map of the world's largest oil spills.
Courtesy 84userLast week, BP attempted again to stop the oil flowing from the Deepwater Horizon borehole, this time through something called the "Top Kill" method. BP engineers hoped to slow the oil by pumping heavy drilling mud into the hole, and then cement everything shut. (Drilling mud is used by drilling rigs to cool the equipment, wash away bits of rock, and counteract the upward pressure of underground gas and oil.)
Things seemed to be going well—underwater fountains of mud appeared to have replaced the oil leaking from the well—and then...
BP announced on Friday that despite pumping 30,000 barrels of drilling mud into the well, the oil couldn't be stopped, and so the attempt to "top kill" the well was a failure. Nuts.
BP already has yet a new plan, which sounds kind of like one of the first plans; they're putting another cap over the leak, to contain the spill, and siphon off most of the oil.
This time, they're going to be cutting off the remains of the riser pipe and the top of the blowout preventer assembly, to have a single, clean source of the leak. Then they will be lowering the "Lower Marine Riser Package (LMRP) Cap Containment System."
The LMRP is supposed to seal around the severed pipe, and it will send the oil up a riser to another drill ship. (The operation should look something like this.)
In the meantime, BP is continuing to drill a relief well to intercept the original borehole, which should allow them to clog it up. As of Friday, the relief well was at 12,090 feet. The press release on the status of the relief well didn't say how deep it would have to be before it intercepted the original hole, however. Less than 18,000 feet, I suppose, seeing as how that was supposed to be the depth of the reservoir (I think).
Check back on Science Buzz for updates on the oil spill.