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You might not think of volcanoes as particularly musical, but they do actually generate infrasound! And scientists may be able to use that sound to help predict when a volcano is about to erupt.

Hosted by: Michael Aranda.

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Scientists have used a “galaxy-sized” space observatory to find possible hints of a unique signal from gravitational waves, or the powerful ripples that course through the universe and warp the fabric of space and time itself.

The new findings, which appeared recently in The Astrophysical Journal Letters, hail from a U.S. and Canadian project called the North American Nanohertz Observatory for Gravitational Waves (NANOGrav).

For over 13 years, NANOGrav researchers have pored over the light streaming from dozens of pulsars spread throughout the Milky Way Galaxy to try to detect a “gravitational wave background.” That’s what scientists call the steady flux of gravitational radiation that, according to theory, washes over Earth on a constant basis. The team hasn’t yet pinpointed that target, but it’s getting closer than ever before, said Joseph Simon, an astrophysicist at the University of Colorado Boulder and lead author of the new paper.

A team led by University of Minnesota Twin Cities researchers has discovered a groundbreaking one-step process for creating materials with unique properties, called metamaterials. Their results show the realistic possibility of designing similar self-assembled structures with the potential of creating “built-to-order” nanostructures for wide application in electronics and optical devices.

The research was published and featured on the cover of Nano Letters, a peer-reviewed scientific journal published by the American Chemical Society.

In general, metamaterials are made in the lab so as to provide specific physical, chemical, electrical, and optical properties otherwise impossible to find in naturally occurring materials. These materials can have which make them ideal for a variety of applications from optical filters and medical devices to aircraft soundproofing and infrastructure monitoring. Usually these nano-scale materials are painstakingly produced in a specialized clean room environment over days and weeks in a multi-step fabrication process.

Summary: A newly developed technique dubbed NeuroPAL is helping researchers investigate the dynamics of neural networks in the nervous system of microscopic worms.

Source: Columbia University.

The human brain contains approximately 86 billion neurons, or nerve cells, woven together by an estimated 100 trillion connections, or synapses. Each cell has a role that helps us to move muscles, process our environment, form memories, and much more.

Circa 2014


A NASA study has recently concluded that the “Cannae Drive,” a disruptive new method of space propulsion, can produce small amounts of thrust without the use of propellant, in apparent discordance with Newton’s third law. According to its inventor, the device can harness microwave radiation inside a resonator, turning electricity into a net thrust. If further verified and perfected, the advance could revolutionize the space industry, dramatically cutting costs for both missions in deep space and satellites in Earth orbit.

The basic principle behind space propulsion is very simple: for every action, there is an equal and opposite reaction. Use a rocket engine to throw mass one way, get propelled the other way. And according to the law of conservation of momentum, the more mass you throw behind you and the faster you throw it, the stronger your forward thrust will be.

One consequence for space travel is that, to counter Earth’s gravity and reach orbital velocity, rockets need to carry a very large amount of propellant: For instance, in the now-retired Space Shuttle, the mass of the fuel was almost twenty times greater than the payload itself. In satellites the impact is smaller, but still very significant: for geostationary satellites, fuel can make up as much as half the launch weight, and that makes them more expensive to launch and operate.