Anyone want to try and guess why blowing on frikkin’ molten Aluminum (or slapping it with a glove) didn’t put the fire out? Bueller?
(Here Comes the Sun) (-1)
Why is the Earth moving away from the sun?
Short answer: tidal friction, the same reason the moon is receding from us.
But there’s a “what the?” in the story.
[T]he sun-Earth distance has been pegged with remarkable accuracy. The current value stands at 149,597,870.696 kilometres.
Having such a precise yardstick allowed Russian dynamicists Gregoriy A. Krasinsky and Victor A. Brumberg to calculate, in 2004, that the sun and Earth are gradually moving apart. It’s not much – just 15 cm per year – but since that’s 100 times greater than the measurement error, something must really be pushing Earth outward.
No error is reported, but presumably the error is in the last digit of the value, 0.001 km. One one-thousandth of a kilometer is a meter. 15 cm is smaller than that. If the error is as was reported, it should be a few millimeters. If that’s the error, why isn’t the distance known and reported to that level?
Not Subject to the EEOC
We’re rearranging the lab, and clearing out some old equipment, including taking down part of the original Cesium Fountain laser layout (which uses a lot of optical table space). A colleague was moving a rack, and wanted to know where it should go. I suggested next to a hard place, but leaving a gap, so something could go in between. Badump-ching!
Fortunately for me, puns are not inherently part of the “creating hostile work environment” definition which applies to Federal employees.
Anyway. part of the laser system of the Cesium fountain (the slightly less dense optics forest on the far side of the table in the picture) is no more. Walking into the lab to see that half the table bare was a bit traumatic for me, since it’s the experiment I raised from a pup. But my colleagues said the setup isn’t really gone — they moved that part of the experiment to a very nice lab out on a farm, and assured me that the optics were much happier there, because it has very nice temperature control and people to clean the mirrors and keep everything aligned. So I feel a lot better about that.
Smashing Pumpkins. Or Something.
It’s not the squirrel smasher, but it’s close. Abstruse Goose does the Toad Totaler
But … stationary target? It would be much more efficient to have the lab frame also be the center-of-mass frame (i.e. counter-propagating frogs)
Wheel … of … Falkirk!
These caissons always weigh the same whether or not they are carrying their combined capacity of 600 tonnes (590 LT; 660 ST) of floating canal barges as, according to Archimedes’ principle, floating objects displace their own weight in water, so when the boat enters, the amount of water leaving the caisson weighs exactly the same as the boat. This keeps the wheel balanced and so, despite its enormous mass, it rotates through 180° in five and a half minutes while using very little power.
Short time-lapse video of the wheel in action
Healthy Graphing Technique
An interesting graph of life expectancy vs per-capita income, for a bunch of different countries around the world. What is so trés cool is that you can animate it to run it from 1800 to the present. France does a meteoric rise very early on with no change in income, war participants take hits in life expectancy, and basically the whole world does the Time Warp (it’s just a jump to the left) in 1929.
Technically, it's not Plastic Surgery
instructables: Gummi Bear Surgery
NOTE: This Instructable contains graphic images of Gummi Bear surgeries.
The Search for the Dragon(fly) Warrior
One of the questions I was asked in my most recent adoption was what I would do if I were not a physicist. I’m pretty sure I would do something in science, and I have an interest in evolution and paleontology. The stumbling block to going in that direction was the squishy part of biology — when I was in school, I was pretty sure animal dissection would start by making me weak-in-the-knees, followed by me throwing up, and I had no desire to test that prediction. Consequently, I haven’t studied a whole lot of biology, including entomology.
But dragonflies are pretty fascinating. They don’t fall under the “bugs to be avoided” category — not gross house-invaders, nor do they want to sting me. I had no idea that they flap their sets of wings out of phase, though it makes sense (if it were in phase, why not just have a bigger wing?) But I have some shots where it looks like maybe the two sets are at slight different frequencies, so the phase changes. I also didn’t realize how much they glide when they fly. And the flapping is low enough in frequency that it shows up well on a high-speed camera — a much lower pitch than many other insects.
It’s also really hard to pan a camera to follow them. I think I saw six distinct species; these were the biggest and flew high, while a few others tended to hug the ground, and yet others I only saw in the woods.
Gelett Burgess's Stove
I never saw a purple cow;
I never hope to see one;
but I can tell you anyhow;
I’d rather see than be one!
I modified a webcam to allow IR photography, but didn’t think to take a picture like the one Matt has displayed, in which a stove’s heating element glows purple (when viewed with his camera), just as it starts becoming incandescent. I have a gas stove.
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Couldn’t remember where the DJIA has been hanging out recently.
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