More materials trivia
DID YOU KNOW?
The US Navy launched 480 million copper needles into orbit
In the late 1950s the US Military enacted a contingency plan in the event their communication cables were cut. They launched 480 million copper needles into orbit in an attempt to bolster the communication properties of the existent ionosphere. Each needle was 1.8*10^(-3) cm, half the length of the 8,000 MHz microwaves used in long distance communications. While briefly successful, within a few months the needles dispersed enough to render their effects negligible. With the rise of satellite communications the project died off in favor of more effective permanent communication methods.
The world's oldest nuclear reactor opterated for 150 million years
While processing ore in Gabon, decreased amounts of Uranium 235 were discovered. Upon closer inspection of the source, scientists discovered that a cycle of flowing water through the uranium rich soil had produced a naturally occurring reactor. This process involved water seeping through crevices filling the gaps between the uranium deposits, and acting as a "neutron moderator." This slowed down the neutrons enough to allow them to hit-and-split other nuclei. When the reaction caused a sufficient heat increase, the water boiled off, removing the neutron moderator, and stopping the process. Then the cavity would slowly refill with water during the cooling period, starting the cycle again.
New solid carbon will transform the world we live in
A new aerogel has just shattered records for the least dense solid. Clocking in at just 0.16 mg/cubic centimeter, the new aerogel is less dense than helium. It is developed by freeze drying solutions of carbon nanotubes and graphene. This easily producible aerogel could be used to clean oil spills, provide insulation, or trap space dust.
Did you know about Helium and the third sound?
Normal liquids experience viscous drag when the fluid flows, causing it to lose energy. One of the unique properties found in Helium and other superfluids is the ability to flow without encountering this viscous force and loss of energy. As a consequence, rather than propagating through compressive effects commonly found, the Helium can transport sound in oscillating waves. These waves are visually similar to shallow water waves that you might see on a beach.
Gold is heavier than the movies portray
In many old western movies, the “bad guys” are shown loading gold bars into saddlebags or wheel barrels. This is a bit far-fetched because many of the bars at the sizes shown would weigh close to 80 or 90 lb. In fact, the density of gold and platinum is almost twice that of lead, whose density = 11.34 gm/cm3. A saddlebag filled with these bars of golg plus the rider would be too much for the horse, or a human, to carry. Most people do not have the opportunity to actually lift a gold bar, so Hollywood perpetuates the myth.