• The Environment

    The Science of Changing Your Oil

    By Posted on 8.14.2008 4 Comments


    Dear EarthTalk: How often do I really need to change my car's oil? Conventional wisdom has always put it at every 3,000 miles to prevent engine wear, but isn't changing oil that frequently wasteful and unnecessary? Also, what is the "greenest" and longest-lasting oil I should use? -- Vic Roberts, Lincoln, MA

    8.17.2008 at 03:29pm - Comment by Light

    ford2go - Actually, you are wrong. Mineral Oil does wear out and is specifically the reason it needs changing. It wears out due to the heat of the engine and the chemical effect of the blow-by gasses from the combustion chamber to the crankcase. Synthetic oil is made from gas products and is far more pure than regular mineral oil. Synthetic oil was specifically designed for use in aircraft turbines which has to withstand very high temperatures and high speed friction without breaking down... something regular mineral oil had repeatedly failed to do. The main reason to change the oil when using synthetics is because it gets dirty, the detergents in the oil are no longer effective, and oil filter by-pass valve trips on. Next time you have "information" on something, please be sure to make sure oyu know what you're talking about. The mere fact you mentioned you haven't "seen" any evidence on the differences of these two kinds of oils says you don't haven't read up on the subject. Check out Wikipedia or even google "synthetic oil" and you'll get the information you're missing.

  • Science

    Frogs on the Verge of a Major Extinction

    By Posted on 8.15.2008 6 Comments

    Lots of amphibians (a third to a half of all species) are dying, and their deaths are the breaking-edge of what many scientists are calling the first mass extinction since the dinosaurs checked out 65 million years ago, researchers say in a new paper published online in the Journal Proceedings of the National Academy of Sciences.

    8.17.2008 at 03:03pm - Comment by Light

    So lemme get this straight... The extinction could have started happening over 10,000 years ago, but somehow man-driven global warming in the last 20 years is the cause.... WHAT? But we don't really know when it started so we're gonna say the bad man did it. What happened to the iota of scientific rigor in this magazine? The fact of the matter is that the climate has never STOPPED changing. and organisms will be forced to adapt or die as usual.

  • Science

    The Hyper-Sub

    By Posted on 7.16.2008 7 Comments

    Nautical engineers have long dreamed of a craft that could race across wave tops like a speedboat and seconds later dive beneath them like a submarine. But crossing the two breeds presents a catch-22: Subs need heft to sink, but speedboats need to be lightweight to go fast. With an investment of nearly $2 million and years of research, former auto-shop owner Reynolds Marion of Lake City, Florida, has finally hit on a solution, a machine he’s dubbed the Hyper-Submersible Powerboat. When complete, it will reach speeds of up to 45 mph and dive down to 1,200 feet.

    7.17.2008 at 12:56pm - Comment by Light

    That's right! We shouldn't ever do anything cool or new because drug smugglers might use it! The drug war is a crock. Legalize, tax, and regulate. People will abuse it anyway. Look at prescription meds. Some geniuses even huff paint. You'll never stop people from doing what they want or trying to get intoxicated. You'd think the repeal of prohibition would have been a clue. Anyhow, I better stop. Some DEA agents have families to feed and doors to kick down in a paramilitary raid. All in the name of keeping you from harming yourself!



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