Finding Exoplanet6

Finding Exoplanet6 - early-June 2011 have been found this...

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Finding Exoplanets Detecting planets around other stars ( exoplanets ) is a difficult project requiring very careful observations. At first finding planets might seem a simple thing to do---take pictures of stars and look for small faint things orbiting them. A planet would indeed be a faint: a billion or more times fainter than a star in the visible band---the glare of the starlight would wash out the feeble light of a planet. The direct imaging technique of finding planets would be better accomplished in the infrared band because the planet's thermal spectrum would have maximum emission in the infrared band. Also, stars produce less infrared energy than visible band energy---a planet would only be ten to a hundred thousand times fainter than the star. The planet would still be very faint, but at least the contrast ratio is improved by many thousands of times. The direct imaging technique is able to find jovian planets far from their parent stars. Twenty-four planets (as of
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Unformatted text preview: early-June 2011) have been found this way. Some of the planets imaged are very young and still quite warm from their formation. Therefore, the young planets are quite bright in the infrared and easier to detect. Some planets have been imaged by blocking the light from the much brighter star with a device called a coronograph so that the feeble light from the planet can be detected. Use of a coronograph was essential to create the first visible light (optical) image of a planet: that orbiting the very bright star, Fomalhaut, shown below. The black area in the center is the coronograph, the white dot shows the location of the star, the ring is a dusty debris disk analogous to our solar system's Kuiper Belt (but much further out), the small white box shows the location of the planet some 115 AU from its star, and the inset shows its motion over two years of its entire 872-year orbit. Its motion proved it was an object orbiting the star....
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Finding Exoplanet6 - early-June 2011 have been found this...

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