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Explanation prominences prominences are huge clouds

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Explanation: Prominences. Prominences are huge clouds of relatively cool dense plasma suspended in the Sun's hot, thin corona. They have been viewed telescopically during solar eclipses for centuries. They appear as red flame-like protuberances rising above the limb of the sun. Prominences can now be viewed at any time on spectroheliograms. Note that pictures such as the one above are taken in a specific wavelength of light, in this case the wavelength emitted by a type of ionized helium. The chromospheric emission lines in a small region of the sun will occasionally brighten up to unusually high intensity causing a ___________. Explanation: Flare. Flares appear as intensely bright spots, usually in the vicinity of a sunspot. A flare usually reaches its maximum intensity within a few minutes after its inception and fades out more slowly. The closest star after our sun is ______ light years away. Explanation: 4.2 light years. The closest star is Proxima Centauri, which is about 4.2 light years away from our sun. Stars that vary in light are called ____________ stars and are designated in order of time of discovery in the constellation in which they occur. Explanation: Variable. The luminosity of variable stars makes them different from the more stable ones that comprise the majority of stars. Once discovered, they are named and/or designated by a letter followed by the constellation where it appears. For example, the first star designated as a variable star in the Coronae Borealis constellation would be named the R Coronae Borealis. Subsequently discovered variable stars in the same constellation would be designated with the letters S, T, and so on. The three techniques most commonly employed to determine the apparent _______________ of a variable star are: 1) estimating the magnitude of the variable by visual observation through the telescope; 2) comparing the magnitude of the variable star to other stars; 3) determining the magnitude of the star by photoelectric photometry. Explanation: Brightness. The magnitude of a variable star changes with time and this is referred to as the light curve of that star. One of the types of variable stars is the ______________ variable; they periodically expand and contract, affecting size and light. Pulsating. These stars comprise the largest number of variable stars known. They expand and contract, pulsating in size as well as in light.
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A second type of variable stars is the _______________ variables, which are stars that show sudden outbursts of light. Explanation: Eruptive. These sudden, unpredictable outbursts of light or diminutions of light make them the least common of the variable stars. _______________ variables are binary stars whose orbits of mutual revolution are in our line of sight and which periodically eclipse each other. Explanation: Eclipsing. Eclipsing variables are not true variable stars, but are classified as such because their luminosity changes during eclipses.
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