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The Solar Death Ray
Ant writes the "Solar Death Ray is made of 112 mirrors mounted on a platform 4 feet wide and 6 feet tall. Each mirror is a square roughly 3.5 inches on edge. All these mirrors focus the sun to a single spot 5 feet, 6 inches from the mirror platform. A wooden fork extends from the mirror base to the area near the focus and serves as a mounting point for Solar Death Ray targets. The mirror platform is mounted to the support frame on a pivot that allows the platform to be angled. The whole system is mounted on a set of wheels. The goal of the Web site was to show the results of the targeted items when the solar death ray was used."
Ummmm, shields aren't concave, they're convex. I suppose they could be turned around, but then the handles and stuff counteract the effectiveness of the "focusing". Also, focusing only really helps at near the focal length. Beyond twice the focal length it should disperse rays that started as parallel.
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Why, you're absolutely right. It's a myth. This guy must have FAKED all those photos!
Although I found the justification for the Hootie and the Blowfish tape hilarious, he should be flogged with a bamboo cane for burning that tetris disk. That thing was a fucking museum piece!
They were attempting to replicate what Greeks could have reasonably done with the technology they had available. The myth isn't that you can use a bunch of mirrors to set things on fire. The myth is that Greeks 2500 years ago were able fire ships some distance away in a harbor. They wouldn't have been using any sort parabolic mirror and even a concave one of any reflectivity at all would be a serious stretch. The Mythbusters did a decent job of showing that the ancient Greeks probably didn't have sufficient mastery of optics to make a practical sunlight weapon.
Mythbusters is far too quick to "bust" myths that are actually true to some extent. They make a couple of (usually poorly designed) tries to replicate the circumstances, and then when their small number of tests fail they declare the myth "busted".
This is a perfect example. Mythbusters claims to have "busted" the solar death ray myth, yet the guys in this article were successful in lighting shop rags, pairs of old jeans, boardgames, etc on fire, and have pictures to prove it.
I hate to be the one to point this out, but um. They haven't actually killed anything. This more accurately should be called a Solar Plastic-Melting Ray.
No, he did kill some something: Army men. Okay, maybe they are made of plastic, but they're still men.
24 beers in a case, 24 hours in a day. Coincidence? I think not!
You'd be right if there were no atmosphere.
A parabolic array only matters when you are trying to focus a signal. The Greeks were only interested in energy, and had no concern for phases. Therefore they don't need anything other than clear line of sight to the target for everyone. Each person just has to figure out which of the (many) bright spots is the one they control, and keep that more or less on the target. So long as the average energy reaching the target spot is enough it doesn't matter if many are not on target at any particular moment.