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The Extreme Ultraviolet Variability Experiment (EVE)
Dean Pesnell: Solar irradiance is the energy hitting the earth from the sun. We have different kinds of solar irradiance. We have heat solar irradiance, which is the infrared radiation. We have the visible light, which is what we can use to see and what makes plants grow. We also have ultraviolet light, which is absorbed by our ozone layer, and we also have x-ray and extreme ultraviolet, which is quite harmful and thankfully absorbed much higher up in our atmosphere. EVE is the Extreme Ultraviolet Variability Experiment.
It will measure the solar irradiance in the extreme ultraviolet, which is very short wavelengths that are absorbed completely by the Earth's atmosphere and never make it to the surface. They also are quite deadly, and can hurt people and electronics that are out in space. They cause the atmosphere to heat up and expand and bring down spacecraft. And also, it causes radio communications to be interfered with.
EVE will measure the solar irradiance at these wavelengths very rapidly-- about every ten seconds--allowing us to use that for warning people about the dangers of flares, for putting them into the models that tell us what's happening to the atmosphere, and to also allow people that are doing radio communications and navigation to know that there could be a problem with their system because of what the sun just did.
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