The most powerful fuels in use today are characterized by a "specific impulse" - a measure, in seconds, of how fast a propellant is fired from the back of a rocket - of 450 seconds. "And if you convert it back to molecular hydrogen, all that energy is released, so it would make it the most powerful rocket propellant known to man, and could revolutionize rocketry." "It takes a tremendous amount of energy to make metallic hydrogen," Silvera explained. Though it has the potential to transform life on Earth, metallic hydrogen could also play a key role in helping humans explore the far reaches of space, as the most powerful rocket propellant yet discovered. The material could also provide major improvements in energy production and storage - because superconductors have zero resistance energy could be stored by maintaining currents in superconducting coils, and then be used when needed. "As much as 15 percent of energy is lost to dissipation during transmission, so if you could make wires from this material and use them in the electrical grid, it could change that story."Īmong the holy grails of physics, a room temperature superconductor, Dias said, could radically change our transportation system, making magnetic levitation of high-speed trains possible, as well as making electric cars more efficient and improving the performance of many electronic devices. Understanding whether the material is stable is important, Silvera said, because predictions suggest metallic hydrogen could act as a superconductor at room temperatures.
"That means if you take the pressure off, it will stay metallic, similar to the way diamonds form from graphite under intense heat and pressure, but remains a diamond when that pressure and heat is removed." "One prediction that's very important is metallic hydrogen is predicted to be meta-stable," Silvera said. While the work offers an important new window into understanding the general properties of hydrogen, it also offers tantalizing hints at potentially revolutionary new materials. At those extreme pressures, Silvera explained, solid molecular hydrogen -which consists of molecules on the lattice sites of the solid - breaks down, and the tightly bound molecules dissociate to transforms into atomic hydrogen, which is a metal. To create it, Silvera and Dias squeezed a tiny hydrogen sample at 495 gigapascal, or more than 71.7 million pounds-per-square inch - greater than the pressure at the center of the Earth. "It's the first-ever sample of metallic hydrogen on Earth, so when you're looking at it, you're looking at something that's never existed before." "This is the holy grail of high-pressure physics," Silvera said. The creation of the rare material is described in a January 26 paper published in Science. In addition to helping scientists answer fundamental questions about the nature of matter, the material is theorized to have a wide range of applications, including as a room-temperature superconductor. Cabot Professor of the Natural Sciences Isaac Silvera and post-doctoral fellow Ranga Dias. The material - atomic metallic hydrogen - was created by Thomas D. Nearly a century after it was theorized, Harvard scientists have succeeded in creating the rarest - and potentially one of the most valuable - materials on the planet. Lab-Made 'Metallic Hydrogen' Could Revolutionize Rocket Fuel Diamond anvils being used to put pressure on hydrogen sample
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