Nuts and Volts - December 2015

World’s Most Powerful Laser (Sort Of)

The Institute of Laser Engineering (ILE) at Osaka University ( www.osaka- u.ac.jp/en) has announced the successful firing of an enhanced version of its Laser for Fast Ignition Experiment (LFEX), delivering two petawatts (i.e.,

2,000 trillion watts) of power. Using this laser, it is possible to generate a range of high energy quantum beams, including electrons, ions, gamma rays, neutrons, and positrons.

This is said to be a big step forward for “creating such new fundamental technologies as cancer therapy for medical applications and non-destructive inspection of bridges and buildings; to contribute to our ... longevity, safety, and security; and for the realization of fast ignition as an energy resource.” The fast ignition scheme proposed by ILE is also expected to produce fusion energy from a relatively small laser system, which could produce a breakthrough in laser fusion.

The researchers proudly noted that two petawatts is equivalent to 1,000 times the total power consumed by the entire world. This is an impressive number, but one shouldn’t forget that wattage without reference to time doesn’t tell us much about the total energy usage, and this zap lasted only one trillionth of a second. The total energy needed for the beam is only enough to power a microwave oven for a couple seconds. Still, you probably don’t want to look directly into the beam. ▲

ADVANCED TECHNOLOGY

Looney Tonnes

When 3D printers began to surface, we noted here that users had only begun to imagine the plethora of possible applications. Proving the point, it was recently reported that NASA’s Solar System Exploration Research Virtual Institute ( sservi.nasa.gov) is kicking around the idea of building a complete lunar base that way. Apparently, some scientists were thinking about solving the problem of lugging the construction materials 238,000 miles, and it occurred to them that printing it using local materials (lunar dust) might be a better approach.

The European Space Agency (ESA) liked the idea and is collaborating with architects to see how and if it can be done. Reportedly, they are now thinking in terms of a weight-bearing “catenary” dome design that employs a cellular structured wall to shield pressurized inflatable shelter for astronauts and a hollow closed-cell structure to add strength and weight.

According to ESA, “a mobile printing array of nozzles on a 6 m frame sprays a binding solution onto a sand-like building material. First, the simulated lunar material is mixed with magnesium oxide to turn it into ‘paper’ to print with. Then, for the structural ‘ink,’ a binding salt is applied to convert the material to a stone-like solid.” The agency has already demonstrated the ability to print stone-like building blocks that weigh 1.5 tonnes (1.65 tons). Envisioned is a next-gen printer that can attain print speeds of 3. 5 m per hour, so an entire building could be completed in about a week. What happens if it is successful on the lunar surface? Next stop, Mars. ▲ ■ BY JEFF ECKERT TECHKNOWLEDGEY 2015