National Aeronautics and Space Administration. This Doppler-radar image seen on TV weather news uses microwaves for local weather forecasting. Shown here is Hurricane Claudette's eye-wall making landfall. Credit: NOAA.
This image shows sea ice breaking off the shores of Alaska. This is an image of the Amazon River in Brazil. It also used awavelengthin the L-band of the microwave spectrum. Here we see a computerenhanced radarimage of some mountains on the edge of Salt Lake City, Utah.
Since warm water is less dense than cold water, areas with a highersea surface tend to be warmer than lower areas. The sea surface height image page 12 shows an area of warm water in the central and eastern Pacific Ocean thatis about 10 to 18 centimeters higher than normal. Electromagnetic Spectrum Series Series Homepage.
Infrared Waves. Reflected Near-Infrared. Visible Light. Ultraviolet Waves. Earth's Radiation Budget. Diagram of the Electromagnetic Spectrum. Chocolate melts at a much lower temperature about 80 degrees Fahrenheit which means melting a peanut cluster bar with microwaves was much more remarkable. Understandably curious just what the heck had happened, Spencer ran another test with the magnetron. This time he put an egg underneath the tube.
Moments later, it exploded, covering his face in egg. The following day, Percy Spencer brought in corn kernels, popped them with his new invention, and shared some popcorn with the entire office.
The microwave oven was born. At this point you might be wondering: How did Spencer know cooking with microwaves was safe? According to his grandson, he didn't. Today, we know that the low doses of electromagnetic radiation emitted by microwaves are generally considered safe though, the FDA admits that no studies have been done to assess the impact of low levels of microwaves on humans over time, and there are those who still firmly believe microwaves are killing us.
But back in the s, this information was not available. In , just a year after Spencer's snack food serendipity, the first commercial microwave oven hit the market. Needless to say, it wasn't a big seller. The first domestic microwave was introduced in , but it too failed to launch because it was expensive and because microwave technology was still an unknown.
It wasn't until , two decades after its invention, that the microwave oven finally caught on in American homes in the form of Amana's compact "Radarange. Today, Rod Spencer Jr. He's writing a book about his grandfather. I grew up with so many of them, my head is full. Some of the stuff he did - he was crazy, he was smart and everyone loved him.
Type keyword s to search. Today's Top Stories. In , for example, Raytheon researcher John M. Still, Percy Spencer was in a position to trigger the company into exploiting the discovery and his participation was a key contribution. The first microwave ovens from Raytheon were intended for use in restaurants and on airplanes. They were massive, expensive appliances built around 1.
By , Raytheon had begun licensing its microwave technology, and the first microwave oven designed for consumers went on sale from Tappan. As microwaves became more common throughout the s, concerns arose about the effects of microwave radiation on humans, as the New York Times described in :.
Government and industry soon answered. All this has not shaken the resolve of Consumers Union by one milliwatt. For consumers, he said, the temporary solution to the complex problem is to beware the microwave oven. Fortunately, here in the present, we have RF radiation safety figured out. Part of a continuing series looking at old photographs that embrace the boundless potential of technology, with unintentionally hilarious effect.
The HX cipher machine is an electromechanical, rotor-based system designed and built by Crypto AG. The machine uses nine rotors [center right] to encrypt messages. A dual paper-tape printer is at the upper left. Growing up in New York City, I always wanted to be a spy. But when I graduated from college in January , the Cold War and Vietnam War were raging, and spying seemed like a risky career choice. So I became an electrical engineer, working on real-time spectrum analyzers for a U.
I was fascinated. Some years later, I had the good fortune of visiting the huge headquarters of the cipher machine company Crypto AG CAG , in Steinhausen, Switzerland, and befriending a high-level cryptographer there.
My friend gave me an internal history of the company written by its founder, Boris Hagelin. It mentioned a cipher machine, the HX Like the Enigma, the HX was an electromechanical cipher system known as a rotor machine.
It was the only electromechanical rotor machine ever built by CAG, and it was much more advanced and secure than even the famous Enigmas. In fact, it was arguably the most secure rotor machine ever built.
I longed to get my hands on one, but I doubted I ever would. Fast forward to I'm in a dingy third subbasement at a French military communications base. Accompanied by two-star generals and communications officers, I enter a secured room filled with ancient military radios and cipher machines. I am amazed to see a Crypto AG HX, unrecognized for decades and consigned to a dusty, dimly lit shelf. I carefully extract the kilogram pound machine.
There's a hand crank on the right side, enabling the machine to operate away from mains power. As I cautiously turn it, while typing on the mechanical keyboard, the nine rotors advance, and embossed printing wheels feebly strike a paper tape. I decided on the spot to do everything in my power to find an HX that I could restore to working order.
If you've never heard of the HX until just now, don't feel bad. Most professional cryptographers have never heard of it. Yet it was so secure that its invention alarmed William Friedman, one of the greatest cryptanalysts ever and, in the early s, the first chief cryptologist of the U.
After reading a Hagelin patent more on that later , Friedman realized that the HX, then under development, was, if anything, more secure than the NSA's own KL-7 , then considered unbreakable. The reasons for Friedman's anxiety are easy enough to understand. The HX had about 10 possible key combinations; in modern terms, that's equivalent to a 2,bit binary key.
For comparison, the Advanced Encryption Standard , which is used today to protect sensitive information in government, banking, and many other sectors, typically uses a or a bit key. In the center of the cast-aluminum base of the HX cipher machine is a precision Swiss-made direct-current gear motor. Also visible is the power supply [lower right] and the function switch [left], which is used to select the operating mode—for example, encryption or decryption. Peter Adams.
A total of 12 different rotors are available for the HX, of which nine are used at any one time. Current flows into one of 41 gold-plated contacts on the smaller-diameter side of the rotor, through a conductor inside the rotor, out through a gold-plated contact on the other side, and then into the next rotor. The incrementing of each rotor is programmed by setting pins, which are just visible in the horizontal rotor. Just as worrisome was that CAG was a privately owned Swiss company, selling to any government, business, or individual.
But traffic encrypted by the HX would be unbreakable. Friedman and Hagelin were good friends. During World War II, Friedman had helped make Hagelin a very wealthy man by suggesting changes to one of Hagelin's cipher machines, which paved the way for the U.
Army to license Hagelin's patents. The resulting machine, the MB , became a workhorse during the war, with some , units fielded. Hagelin agreed not to sell his most secure machines to countries specified by U.
He convinced Hagelin not to manufacture the new device, even though the machine had taken more than a decade to design and only about 15 had been built, most of them for the French army. However, was an interesting year in cryptography. Machine encryption was approaching a crossroads; it was starting to become clear that the future belonged to electronic encipherment. Even a great rotor machine like the HX would soon be obsolete.
That was a challenge for CAG, which had never built an electronic cipher machine. Introduced in , the machine was a failure.
Also in , Hagelin's son Bo, who was the company's sales manager for the Americas and who had opposed the transaction, died in a car crash near Washington, D.
Although the H was a failure, it was succeeded by a machine called the H, of which thousands were sold. The H was designed with NSA assistance. To generate random numbers, it used multiple shift registers based on the then-emerging technology of CMOS electronics. This mathematical algorithm was created by the NSA, which could therefore decrypt any messages enciphered by the machine.
From then on, its electronic machines, such as the HC series, were secretly designed by the NSA, sometimes with the help of corporate partners such as Motorola. This U. The backdooring of all CAG machines continued until , when the company was liquidated. William F. Friedman [top] dominated U. National Security Agency.
His friend Boris Hagelin [bottom], a brilliant Swedish inventor and entrepreneur, founded Crypto AG in in Zug, Switzerland, and built it into the world's largest cipher-machine company. TOP, U. Parts of this story emerged in leaks by CAG employees before and, especially, in a subsequent investigation by the Washington Post and a pair of European broadcasters, Zweites Deutsches Fernsehen , in Germany, and Schweizer Radio und Fernsehen , in Switzerland.
The Post 's article , published on 11 February , touched off firestorms in the fields of cryptology, information security, and intelligence. The revelations badly damaged the Swiss reputation for discretion and dependability. They triggered civil and criminal litigation and an investigation by the Swiss government and, just this past May, led to the resignation of the Swiss intelligence chief Jean-Philippe Gaudin, who had fallen out with the defense minister over how the revelations had been handled.
In fact, there's an interesting parallel to our modern era, in which backdoors are increasingly common and the FBI and other U. Even before these revelations, I was deeply fascinated by the HX, the last of the great rotor machines.
This particular unit, different from the one I had seen a decade before, had been untouched since I immediately began to plan the restoration of this historically resonant machine. People have been using codes and ciphers to protect sensitive information for a couple of thousand years. The first ciphers were based on hand calculations and tables.
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