Andrew Underwood

AT-ST Walker Halloween Costume

Unlike other years, I put lots of time into my Halloween costume this year. I built an All Terrain Scout Transport (AT-ST) Walker from Star Wars out of cardboard, bristle board and blood (and some white out to cover up the blood). The blood was due to stapling my thumb with an ancient staple gun. It has working legs that walk similarly to how a bird would walk, thus the slang for the machine: Chicken Walker.

Here’s a video of it in action.

Right after finishing it.

Physicist David Deutsch Presents at TED

This is pretty good and worthwhile sharing.

Hearing Test

Here is a site that has a bunch of mp3s of different frequencies. You can use these to determine your audible frequency threshold. With my desktop speakers I was able to hear up to 17 000 Hz. Putting on my headphones allowed me to hear up to 23 000 Hz.

The Moon

How big do you think our moon is? Perhaps the size of France… does that sound right? Actually it turns out that it’s about a quarter of the diameter of Earth. This is actually pretty big for a moon, 3476 km accross to be exact. Compare this with Pluto which is 2274 km accross. That means our moon is bigger than a planet! I for one am glad we have it, because without it the earth would not be so steady. The almost perpetual dance our planet and moon engages in keeps us from who knows what weird things a planet with a moving magma core would get up to. It also gives us our tides. When I say ‘almost’ perpetual, it means that our moon is slowly loosing interest in the dance and is drifting off, currently at a rate of about 4 cm a year. The second question to ask is where did we get our moon? It must have always been there and was just one of the planetesimals that formed with the earth and all the other planets and moons at the beginning of the galaxy. That’s what I would have guessed. Another thing could have been that we locked orbits as the moon floated by from who knows where. Turns out that the current theory says that it was actually part of Earth and was blown out when something the size of Mars hit us. I find it ironic how something that sounds so devistating is one of the items in a long list of why we are here.

Solution

In regards to the post below, Jigga came the closest as to identifying what material was in the picture. It’s my desk, or more specifically, the fake wood on it. My Dad was right in that I put my camera up to a microscope to get the image. It works better than I would have imagined, and the microscope I used is one I’ve had for years. It’s 100x and hand held, called the Smart 2. It comes with a base and some slides, but I usually just put it up to things. I had friends who had different versions of this, one combined a microscope and a telescope.

My desk sags under the weight of my computer monitors. The drawers can’t shut properly because of that.

Camera Fun

Does anyone want to hazard a guess as to what this is a picture of? I used my compact digital camera and a mystery optical system. Links to enlarged.