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Last Post 3/30/2017 12:45 PM by  Laurel Rachmeler
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Crystal (D)


3/30/2017 6:31 AM

    what is the largest sunspot ever seen? also, have any sunspots ever been seen on any other suns (stars) other than our own? thanks...
    Tags: sunspots, starspots, largest sunspot

    Lindsay Glesener

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    New Member

    3/30/2017 7:11 AM
    I'm not sure what the largest sunspot is, but an extremely large one showed up on the Sun just a couple years ago. This one was visible on the Sun in late October 2014. It made headlines for being one of the largest every observed, and if you were to look at the Sun using a special viewer (so that you don't hurt your eyes!) you could easily see the large spot.

    Sunspots have also been observed on many other stars. Since spots are darker than the rest of the star, whenever spots are visible the total light we measure from the star is a little less than usual. Stars are rotating (some of them very fast!) just like our Sun, so as the dark spots go around the Sun we see the measured light increase and decrease. It's kind of like a lighthouse, except that the spots are dark instead of light! This technique allows us to measure starspots on many stars. This technique is of great interest in particular because similar techniques are used for planet-finding, and we have to be careful to keep the two factors separate.

    Laurel Rachmeler

    New Member

    New Member

    3/30/2017 12:45 PM
    Spots on other stars are called starspots! They can be much larger than the ones on our sun. Some have been observed that cover more than a quarter of the visible disk! The visible disk is the half of the surface that is facing us. That spot that Lindsay mentioned (Active Region 2192), was the largest sunspot in the last 24 years, and it only covered 0.27% of the visible disk of our sun.
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