Technology

Researchers Develop New Amp to Study the Universe

07.17.12

The new amplifier consists of a superconducting material (niobium titanium nitride) coiled into a double spiral 16 millimeters in diameter. Image credit: NASA/JPL-Caltech › Larger view

Researchers at NASA's Jet Propulsion Laboratory and the California Institute of Technology, both in Pasadena, have developed a new type of amplifier for boosting electrical signals. The device can be used for everything from studying stars, galaxies and black holes to exploring the quantum world and developing quantum computers.

"This amplifier will redefine what it is possible to measure," said Jonas Zmuidzinas, chief technologist at JPL, who is Caltech's Merle Kingsley Professor of Physics and a member of the research team.

An amplifier is a device that increases the strength of a weak signal. "Amplifiers play a basic role in a wide range of scientific measurements and in electronics in general," said Peter Day, a principal scientist at JPL and a visiting associate in physics at Caltech. "For many tasks, current amplifiers are good enough. But for the most demanding applications, the shortcomings of the available technologies limit us." 

One of the key features of the new amplifier is that it incorporates superconductors—materials that allow an electric current to flow with zero resistance when lowered to certain temperatures. For their amplifier, the researchers are using titanium nitride and niobium titanium nitride, which have just the right properties to allow the pump signal to amplify the weak signal.

Although the amplifier has a host of potential applications, the reason the researchers built the device was to help them study the universe. The team built the instrument to boost microwave signals, but the new design can be used to build amplifiers that help astronomers observe in a wide range of wavelengths, from radio waves to X-rays.

"It's hard to predict what all of the applications are going to end up being, but a nearly perfect amplifier is a pretty handy thing to have in your bag of tricks," Zmuidzinas said. And by creating their new device, the researchers have shown that it is indeed possible to build an essentially perfect amplifier. "Our instrument still has a few rough edges that need polishing before we would call it perfect, but we think our results so far show that we can get there."

The team recently described the new instrument in the journal Nature Physics.

In addition to Zmuidzinas and Day, the other authors of the paper are Byeong Ho Eom of Caltech, and Henry LeDuc of JPL. This research was supported by NASA, the Keck Institute for Space Studies, and the JPL Research and Technology Development program. JPL is managed by Caltech for NASA.

Ark full of books to help tide over the digital disaster

Richmond: In a wooden warehouse in this industrial suburb, the 20th century is being stored in case of digital disaster. 
    Forty-foot shipping containers stacked two by two are stuffed with the most enduring, as well as some of the most forgettable, books of the era. Every week, 20,000 new volumes arrive, many of them donations from libraries and universities thrilled to unload material that has no place in the Internet Age. 
    Destined for immortality one day last week were “American Indian Policy in the 20th Century,” “All New Crafts for Halloween,” “The Portable Faulkner,” “What to Do When Your Son or Daughter Divorces” and “Temptation’s Kiss,” a romance. “We want to collect one copy of every book,” said Brewster Kahle, who has spent $3 million to buy and operate this repository situated just north of San Francisco. “You can never tell what is going to paint the portrait of a culture.” 
    As society embraces all forms of digital entertainment, this latter-day Noah is looking the other way. A Silicon Valley entrepreneur who made his fortune selling a datamining company to Amazon-.com in 1999, Kahle founded and runs the Internet Archive, a nonprofit organization devoted to preserving Web pages —150 billion so far — and making texts more widely available. But though he started his archiving in the digital realm, he now wants to save physical texts, too. “We must keep the past even as we’re inventing a new future. If the Library of Alexandria had made a copy of every book and sent it to India or China, we’d have the other works of Aristotle, the other plays of Euripides. One copy in one institution is not good enough,” he said. 
    Kahle had the idea for the archive while working on the Internet Archive, which has digitized two million books. With a deep dedication to traditional printing — one of his sons is named Caslon, after the 18th-century type designer — he abhorred the notion of throwing out a book once it had been scanned. The volume that yielded the digital copy was special. 
    And perhaps essential. What if digitization improves and we need to copy the books again? “Microfilm and microfiche were once a utopian vision of access to all information,” Kahle noted, “but it turned out we were very glad we kept the books.” An obvious model for the repository is the Svalbard Global Seed Vault, which is buried in the Norwegian permafrost and holds 740,000 seed samples as a safety net for biodiversity. But the repository is also an outgrowth of notions that Kahle, 51, has had his entire career. NYT NEWS SERVICE

Record-busting motorbike will be jet engine on wheels

 

RICHARD BROWN is a man with unfinished business. In 1999, he smashed the one-way speed record for a motorbike by hitting 584 kilometres per hour on the salt flats of Bonneville in northern Utah. But his claim on the outright world record - which is based on the average of two runs in opposite directions - was thwarted by technical problems.

Now he is trying again. He hopes to be the first person to exceed 720 km/h on a motorbike while achieving an average two-way speed of at least 640 km/h. Any old bike will not do: he will be using one that is jet-propelled.

While cars used in land-speed-record attempts, like the Bloodhound jet car that will attempt the challenge in 2012, and certain types of boat have taken advantage of jet thrust since the 1950s, all record-breaking motorbikes have used a conventional engine that drives the rear wheel.

This is because it is difficult to pack a jet engine into a two-wheeled frame capable of enormous speed with any degree of safety. Fast cars can be built around old jet fighter engines, but these are far too heavy to fit into a bike that must be balanced by the driver making tiny steering adjustments to the front wheel.

So for his new bike, called Jet Reaction, Brown has redesigned a 930-kilowatt helicopter engine to produce thrust instead of turning a rotor. It was "quite difficult", he says. "One is working with very fine tolerances in very difficult materials. If you get it wrong, destroying the engine is the most likely result."

Brown has also added his own reheat unit, or afterburner. It sprays fuel into the hot exhaust gases, causing it to ignite and generate yet more thrust. The idea sounds simple enough, though he says that getting it to work at something approaching its theoretical potential "requires much more development". The reheat burner sits above two canisters that deploy braking parachutes when needed.

Brown has a track record in ambitious jet engine projects. Following his 1999 record attempt he built a sub-orbital rocket, but the launch in South Africa had to be cancelled. He is also working on a gas-turbine-powered jet pack, similar to one developed by the US military, that he hopes will allow the wearer to remain airborne for 10 minutes.

Brown's 1999 record attempt involved his own Gillette Mach 3 Challenger bike, which featured a custom-built hybrid rocket engine. The attempt failed because soft ground forced the team to use tyres rather than the usual aluminium wheels. The tyres were only designed to withstand speeds of 380 km/h or so. Eventually the massive centrifugal forces on the rear tyre caused it to deflate.

The current motorbike land-speed record, 606 km/h, was set in 2010 by Rocky Robinson on a bike called the Ack Attack Streamliner. Such record-breakers feature elongated metal bodies - as does Jet Reaction - making them look more like giant bullets than motorcycles. They are also fitted with retractable stabilisers for balance when moving slowly or stationary.

Brown expects to carry out trials with Jet Reaction at a UK airfield in March next year, with an attempt on the world record back at the Bonneville salt flats pencilled in for 2013.

It won't be easy, says Mark Chapman, Bloodhound's chief engineer. "The biggest issue is air intake," he says. "You have to be sure the air flow through the jet is stable or the engine could surge, which could be dangerous."