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when i got the news on april 23rd

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earlier this year that a flare had been

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detected by swift and it was coming from

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a nearby

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flare star called dg cvn i was initially

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very surprised

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swift doesn't normally detect flares

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from nearby flare stars and dg cvn

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is a relatively unknown star

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there are a few things we know about dg

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cvn

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it is an m-class star also called a red

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dwarf and is located only about 60 light

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years away

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it's a dim little red star it has a

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luminosity that's about one thousandth

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the luminosity of the sun

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it has a mass that's about one-third the

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mass of the sun

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and a radius that's about one-third the

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radius of the sun

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the largest solar flare ever recorded

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happened on november 4th 2003.

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it was so powerful that it overloaded

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the sensors measuring it but later

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calculations put it at an x-45

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flares are classified according to their

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strength

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the smallest ones are b-class followed

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by c m and x the largest

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an x-45 flare is a very powerful flare

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we can estimate how big the flare on

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dgcvn was with respect to the solar

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scale

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it would have been an x

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100 000

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so this is several orders of magnitude

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larger than the biggest solar flare

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we've ever seen

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the flare that swift triggered on from

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dg cvn was only the beginning of what

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turned out to be a fairly extended

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series of flares a flare event

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if you will that lasted almost 20 days

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this was a very different star than the

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sun so we don't really have to worry

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about this happening in the present day

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sun

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such large events may have occurred in

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the present day sun

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the activity levels are much lower the

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fundamental reason that dg cvn is more

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active in the sun is it's a very young

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star 30 million years it's rapidly

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rotating young stars are born that way

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and rapid rotation is one of the key

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ingredients which powers activity the

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faster the rotation the greater the

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activity

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while not a threat to us the massive

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flares of red dwarf stars can help us

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better understand the flares produced by

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our own sun

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they are also of interest because red

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dwarf stars are often orbited by planets

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some data suggest that 40 percent of red

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dwarfs have super earth type planets

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orbiting in a habitable zone where

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liquid water is possible

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if this is true then they are good

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candidates for supporting life

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however

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the habitable zone around a cool dim

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star like dgcvn is much closer to the

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star than the earth is to the sun

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when planets are closer to their star

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they're more susceptible to anything the

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star does for instance

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if the star flares

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the planet is much closer to the star

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and it can be hit by the radiation

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or the particles that get ejected from

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the star when this flare process happens

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if you happened to be on a planet

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around an m dwarf when one of these