SIlver Cell construction (via The Autralian NAtional University)

Soldiers carry a lot of weight. With radios, night-vision devices, flashlights, communication systems, ammunition, and other basic supplies the weight approaches the point of hurting the person carrying it all. In fact, major-general of the Australian army said, "It's not good for a soldier's back to be carrying that much weight."

One area that can benefit from advancing technology has been the size of the electronics and the power systems. In the distant past, communications were powered by heavy lead-acid batteries. Later came lighter weight battery packs that have been getting smaller and more energy dense every year. The progress does not stop here. The Australian army is testing the possible use of lightweight solar panels, eliminating the need for any large battery pack.

The new solar cells are a bit different than standard silicon based panels. Called "Silver Cells," the panel arranges the photovoltaic elements in thinly sliced pieces, vertically, in a silicon frame. The cells use 90% less silicon than other mono crystalline cells of equivalent output. In other words, the costs are lower.

The elements are 50 to 100mm long, 1 - 2mm wide, and 45micrometers thick. Both sides of the element can absorb light. Due to the bifacial response of the Silver cell, the optimal angles are increased. And the cells work well on curved surfaces. Open circuit voltage of the cell is in the 600 - 700mV range. Connected in series or parallel, for whatever voltage the application needs, the cells are capable of 140 Watts per square meter.

The plan is to cover soldier's helmets, tents, and clothing. Testing will be conducted over a few years before acceptance for true field use. What they will soon discover is that the reflective nature of solar panels will not be good for concealing soldiers or objects. Much like flashing the sun off a mirror at your enemies. I would imagine a whole group of soldiers would look like they are sparkling. Not the most intimidating look out there.

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Serious threat of space debris on the space station
In the past three years the International Space Station (ISS) had to change its orbit five time to avoid orbiting "junk" from ripping right through the station vital and fragile shell. In fact on June 28th astronauts took shelter in a heavily fortified section of the space station as a object was detected only fourteen hours before an expected impact. Although it passed one thousand feet from the outside of the station, the countless objects remain a continuous threat.

Russia has blown up many off their satellites which happen to fall within the ISS orbit band, placing thousands of objects in direct line for impact. In 2007 China demonstrated their capabilities to destroy satellites with the take down of one of their own. Thousands of additional objects have been added to the frey. In 2009 an American and a Russian satellite collided producing thousands more for the orbiting path. In other words, the ISS is under constant danger.

With an estimated 1 in 8 chance of an impact, the ISS may end up becoming a short lived destination for space travelers. There are some thin kevlar based protective shields placed over critical components, they will not be able to protect against larger objects. Perhaps collecting space garbage is imperative.

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Though it may all come too late. The ISS is scheduled to be abandoned in 2020.

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At the IEEE Symposium in Chicago this week, Nasa physicist John J. Chapman suggested that boron could be used as an "aneutronic" fuel, a fusion power source where neutrons carry no more than 1% of the total released energy (Wiki). What he implied was a new type of fusion thruster.

Using an off the shelf laser directed on to a thick metal foil, the energy is used to accelerate protons. The then rush of electrons leaved behind an overly positive charge. Which creates an imbalance with the protons left behind, resulting in a micro explosion. The explosion will send protons from the metal sheet to a second sheet made up of thin sliced Boron-11.

When the protons interact with the Boron-11, carbon nuclei are formed, but then decays to Helium-4 & beryllium nucleuses. All this would then decay to a pair of alpha particles, which is two protons and two neutrons bound together into a particle identical to a helium nucleus (alpha particles are incredibly dangerous to living cells). Each reaction creates 3 alpha particle, and according to Chapman the process is "very efficient." Electromagnetic force would then channel the alpha particles and all matter they touch through a nozzle. Chapman believe that this fusion thruster would be more efficient that current ion propulsion, but does not see his idea emerging for at least another 10 years.

Where would be we if we all did not speculate from time to time?

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