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RADIO AND MICRO WAVES CREATED BY: PAT WILLIS DERK SIEGLER MATT HOPEWELL INTRO
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Formation of Waves If a wave is passing by a point the wavelength is the distance between peaks in the wave, the distance from crest to crest. The frequency is the time interval between passing peaks. Therefore as the wavelength increases, the frequency decreases and vice-versa.
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RADIO WAVES How we view them Where they come from How they are used
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Radio Waves Electromagnetic radiation which has the lowest frequency, the longest wavelength, and is produced by charged particles moving back and forth; the atmosphere of the Earth is transparent to radio waves with wavelengths from a few millimeters to about twenty meters.
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WHERE DO THEY COME FROM? Stars emit energy in every frequency of the electromagnetic spectrum, including radio waves Ice at very low temperatures is a very effective reflector of radio waves because of this, radio waves can be sent off of distant planets and recaptured by the VLA to find ice Solar winds can also be captured as radio waves
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Radio Waves Radio waves can be longer than a football field or as short as a football. Radio waves do more than just bring music to your radio. They also carry signals for your television and cellular phones.
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How We See Radio Waves Radio waves do not occur in the visible spectrum, because of this we use a “False Color” photo to view them. These photos assign a color to a certain wave length and create a color picture to display information. This picture is of an “Einstein Ring.” Einstein theorized that massive objects, such as stars, could bend light rays passing nearby. Pictured here is a distant quasar, whose radio waves are being bent, or “lensed” by a galaxy between it and Earth. This is why there appears to be two quasars.
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WHAT WE SEE Mercury's surface is heated to temperatures nearing 800 degrees Fahrenheit. Microwaves sent from Goldstone bounced off Mercury and were collected at the VLA to produce a radar image of the side of Mercury that was not photographed by Mariner 10. In this image, red indicates strong reflection and yellow, green, and blue, progressively weaker reflection. The bright red dot at the top of the image indicates strong radar reflection at Mercury's north pole."Normal" ice, such as that found on Earth, absorbs radio waves, but ice at very low temperatures is a very effective reflector of radio waves
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The VLA has revealed important details of double-star systems and their interactions, including regions in which material pouring out as part of one star's "stellar wind" is ionized by the high-energy radiation from its companion. WHAT WE SEE
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The Very Large Array: (VLA) In New Mexico Because radio waves are very large, some as long as football fields, they are captured by many telescopes so that a larger picture can be pieced together by the information. This is the where the data is false colored to create visual data from radio waves. VLA
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How waves are used-
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Microwaves Introduction to Microwaves Microwaves are located between radio waves and infrared in the electromagnetic spectrum. The wavelength of microwaves can be anywhere from 1 mm to 30 cm. Uses The longer microwaves, such as the ones about a foot in length, are used to heat food in Microwave ovens. Microwaves are also used to transmit information because they can penetrate clouds, rain, haze, and fog. Even smaller microwaves are used for radar, for things like weather forecasts. A map spanning ten degrees of the microwave sky resolves the microwave background into hot and cold spots. The scale shows what the colors represent in microkelvins.
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Radar Shorter microwaves can be used for remote sensing. This is known as radar. Radar is short for “radio detection and ranging”. Radar can detect objects by transmitting short bursts of microwaves. The microwaves are then reflected back. The strength and origin of these reflections can then be recorded. The Microwave Report The Forecast Doppler Radar is an example of how microwaves are used to to show the weather forecasts.
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Taking a Look at the Beginning -Cosmic Background Radiation Cosmic microwave background radiation fills the entire universe. This Radiation is believed to be a clue to the Beginning of our universe. It is strong evidence for The Big Bang theory. Satellites- The Cosmic Background Explorer(COBE) was the first satellite whose goal was to record Data about the cosmic microwave background. The Microwave Anistropy Probe(MAP is a new NASA explorer which is able to record Data 20 times smaller than COBE was able To record. This will provide a map of the Remnant heat supposedly left from the Big Bang. It should provide answers to many of Our questions about the origin of our universe.
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Things are Heating Up -Microwave Ovens Microwaves can also be used to cook your Food. Water and fat molecules absorb the Energy carried by the microwaves. The Molecules move about faster, so the water Or fat gets hotter. Normal cooking devices Heat the outside of food, while with Microwave ovens, molecules one or two Centimeters below the surface absorb the Microwaves. This helps the food to cook Faster. -Seeing with Microwaves In the same way that they are used in detecting the weather, microwaves can be used to take pictures. We can use microwaves to take Pictures of the earth with satellites in space. The above photo was taken by the JERS Satellite. It is a picture of the Amazon River In Brazil.
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