DVDs and Scramjets

Watch out, there are two competing DVD standards coming out within the next year. Current DVD technology uses red lasers to read the DVD. Both of these new standards use blue lasers to read the DVD. Since blue light has a shorter wavelength then red light (which also explains a blue sky and red sunsets), these new DVDs will be able to store much more then the current DVDs can. Anyone remember VHS vs. Beta? Or Nintendo vs. Sega? Or PC vs. Mac? Hopefully we as consumers won't get burned by this competition.

Ever heard of a scramjet? I heard about it back when it was still in the conceptual stages. The big news is that NASA had their first test flight for their new scramjet plane yesterday (November 17, 2004). They almost reached Mach 10, which is ten times the speed of sound.

Scramjet means "supersonic combustion ramjet." To briefly explain, a large problem with jets and rockets of any kind is that they need to carry a large quantity of oxygen to help ignite their fuel. The idea for this jet is that, once it hits a high enough speed, it can just open a port at the front of the engine and take in oxygen from the air. The oxygen is naturally compressed because the kept is going so fast, so the plane doesn't have to carry extra oxygen anymore. Combine that with a ramjet (which is another tricky explanation) and we have supersonic planes. Good old NASA, what would we do without them?