Monday Science Links

Oops! I thought I'd scheduled this, but obviously hadn't. So here's a just-slightly-late heaping helping of sciency goodness:

• Julianne at Cosmic Variance shares one cool photo:What’s striking about this pair of galaxies is that one of them is partially occluding the other. Galaxies contain a lot of dust which can block light, particularly at optical and bluer wavelengths. Because the background galaxy is relatively smooth, you get a wonderful view of the location of dust in the foreground galaxy. It’s clear from the image that the dust is found waaaaaay out from the center of the galaxy, in spiral arms that go well past one would call the edge of the galaxy (based on where you see light on the un-occulting side of the foreground galaxy, to the right on the image above). It’s rare that you ever find two galaxies of comparable size occulting one another, and rarer still that the alignment is so perfect for tracing out the dust to such large radii.


• A new guy in the science blogosphere, Dr Johnson Haas, who blogs at The Planetologist, talks about US crude reserves: If it were possible to open up enough land and water for drilling in the US to offset our need for foreign oil, why haven’t we plowed ahead with that plan? I doubt hippies could get in the way if the US were actually sitting on that many billions of untapped dollars. Hippies didn’t stop us before. At one time the US was the world’s supplier of oil. We won WWII and strode forward into the 1950s on titan legs powered by Texas crude, then Californian, then Gulf of Mexico-an. We were rolling in oil, until we weren’t. By 1970 it was clear that the party was over, and oil reserves were running down. We’d tapped the primo goods, we had only half our cache left, we were smoking it up a lot faster than we used to, and we began to notice the baggie was running low. So we found some dealers. Namely the Saudis, the Iraqis, the Iranians, the Venezuelans, the Russians, the Canadians, the Mexicans, and basically anyone else on the face of the Earth who was holding.


• Judith at Zenobia: Empress of the East goes much earlier to talk about a different uppity woman:This angry-looking Neanderthal woman had pale skin, freckles, and was a fiery red-head too. This is the first reconstruction of a female Neanderthal to be based in part on ancient DNA evidence. Anthropologists have now gone beyond fossils and are reading the actual genes of an extinct species of human.


• Sean at Cosmic Variance discusses LHC safety: In the latest Science Saturday at Bloggingheads, Jennifer and I zip from the breathtakingly topical — the Large Hadron Collider, what it’s good for, and why you shouldn’t be scared of it — to the profoundly eternal — calculus, and why people are scared of it. I’ve finally settled on a proper response to questions about whether the LHC will destroy the world. (After the initial response, I mean.) It comes in two parts.


• Jennifer at Cocktail Party Physics discusses bells and bell ringing, with a diversion into The Nine Tailors: Bells are fascinating things, right down to how they are made -- or rather, cast, since the process involves pouring molten bell metal into a mold. In The Nine Tailors, the tenor bell is named Tailor Paul, supposedly cast in a field next to the churchyard in 1614. Once the bell has been cast, it can be "tuned" by paring metal off various parts of the bells' soundbow. As for the creation of the mold, that is an equally painstaking process. There is an inner mold, or core, and an outer one (the "cope), both made up of a mixture of clay, cow dung (!) and horse hair. This mud pie is built up into the desired shape, supported by a metal base plate ("strickle"), layer by painstaking layer. After a certain number of layers, the mold is baked in a dry oven until it is hard, then more layers are added, then baked, and so on. Any air pockets or moisture would be bad, as the finished mold would crack when the molten lead is poured into it.

Enjoy!