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People have been

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hunting for sungrazing comets for hundreds of years, but as of

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1979 we only knew of less than a dozen. Today.

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we have seen about 2,500. Why did the number increase?

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Understanding this starts with the Kreutz path. In the

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late 1800s, Heinrich Kreutz observed that many recent comets

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traveling near the sun appeared to follow the same orbit. On this Kreutz

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path, as we've come to call it, it takes the comet about 800 years

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to complete one loop around the sun. While there are other orbits of

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sungrazers, Kreutz comets are the most common. All of the comets

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in this orbit came from a single comet, observed thousands of years ago.

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As the comet moved closer to the sun, the ice binding it

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together evaporated, breaking it into smaller pieces that the sun's gravity

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pulled apart. Every time the comet comes around the Kreutz path, this can

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happened again, resulting in a new generation of comets. It might

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sound like this would clutter the solar system full of comets, but that is not the case.

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Some of the new comets are small enough that they become completely vaporized

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as they approach the sun. There are more comets observed, not because

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there are more in the solar system but because we have better ways to see them.

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Spotting a sungrazer from the ground is difficult because of the blinding sunlight.

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Now, spacecraft designed to observe the sun make the job a lot

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easier. Since the joint ESA/NASA mission SOHO launched in 1995,

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it has shown us thousands more comets than any tool before.

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To date, it has found 2,387 comets.

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With SOHO we can now see the smaller, fainter comets

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close to the sun, just long enough to ad them to our list of sungrazers

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before they vaporize. The spacecraft's data is available online,

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so now, anyone can discover a comet. Roughly 75%

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of these comets have been found by amateur astronomers.

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Other solar observatories, such as NASA's SDO, weren't expected to provide

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good comet observations, but they captured some beautiful images, creating

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more possibilities for comet research using unexpected tools. Now

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that we can observe comets better than ever - who knows? - maybe you

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will spot the next sungrazer.

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beeping

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beeping

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