On the horizon: News from the frontiers of science

Laser harps, stoking clouds, and the power of 'biochar.'

April 16, 2008

Your own Electric light orchestra

If Spock played a futuristic-looking lyre aboard the USS Enterprise, it might look something like the Beamz Music Performance System, a new musical instrument that functions like a laser harp. Fortunately, you don't have to possess the finger expertise of Andreas Vollenweider to play the W-shaped instrument. And the computer-based system doesn't necessarily have to sound like a harp, either.

The principle is simple. The instrument has six invisible lasers that function as strings. Each one is preprogrammed with musical notes or sounds or looped progressions so that the harpist can create a song by triggering beams with a Marcel Marceau-worthy mime of a pluck or strum. The Beamz software comes equipped with a range of musical genres – from heavy metal to classical to bluegrass – so that one can play just about anything short of a kazoo symphony. (For demonstration video, do a YouTube search.)

The Beamz Music Performance System isn't exactly the first electronic instrument that relies on invisible waves. The Theremin, invented in 1919 and most famously utilized in recordings by The Beach Boys, Led Zeppelin, and Goldfrapp, creates squealing and screeching sounds whenever a musician waves his hands near its antenna to modulate the frequency of emitted signals. Even in the right hands, it can sound like an alien death cry. By contrast, the Beamz instrument boasts that it doesn't allow for any bum notes since everything is programmed to be in tune. The system, which debuted this week, retails for about $600 and is only available at The Sharper Image.– Stephen Humphries

Lasers That Stoke the clouds

Ben Franklin had his kites. Jerome Kasparian has his laser – what he and his colleagues hope will become the latest tool in studying lightning and its effects.

Using a powerful, mobile laser on a New Mexico mountaintop, the team sent laser pulses into two thunderheads and triggered electrical discharges.

With improvements, the researchers say, the technique could replace small rockets that trail thin wires as lightning triggers. The rocket-based approach has been used to explore a range of phenomenon – from the physics of lightning itself to the direct and indirect effects it can have on technologies ranging from airliners to power lines. But rockets are expensive and inefficient, averaging one strike for every two launches.

The laser pulses set up strands of hot, electrically charged gas within the cloud. These plasma strands serve as electrical conductors. Based on data from instruments that can monitor a storm's electrical activity, the researchers were able to trigger mini lightning bolts. But the conducting strands did not last long enough for the discharges to travel more than a few yards. The team, based at universities in France and Germany, reported its results in the current issue of Optics Express, an online publication of the Optical Society of America.

New relevance for an ancient farming trick

A millenniums-old fertilizing technique could help play a significant role in restoring nutrient-poor soils while combating global warming, according to a team of scientists from the University of Delaware.

For years, some archaeologists and sustainable-development activists have known of the technique, which uses ground charcoal. It was first uncovered as scientists studied a 1,500-year-old soil-charcoal deposit in the central Amazon. There the soil was enriched by charcoal from tree bark and animal bones. After analyzing it, the scientists found that it was some of the richest soil on the planet.

Typically, farmers in developing countries use compost, animal waste, and plant debris to enrich their land. But these decompose quickly, releasing carbon dioxide into the atmosphere over short time periods. Once it's applied, charcoal, or "biochar," would lock its carbon in the soil for hundreds of years. Moreover, the charcoal has a high nutrient level; it can capture and slowly rerelease water; and in granular form, it keeps soils relatively loose once it's mixed in. The team tested the approach on seedlings and found faster germination and higher growth rates among wheat grown in a soil-biochar mixture, compared with plants grown in biochar-free soil. The group says it is looking for ways to mass-produce biochar relatively cheaply and is undertaking long-term field studies to see how well this approach works on vegetables and other crops.

The researchers – one of several commercial and university-based groups exploring the potential for biochar – reported its results at last week's annual meeting of the American Chemical Society.