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[Music]

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what's up for september

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the moon with mars and venus and a star

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with a planet

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that wasn't on september 6th you'll find

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the moon

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extremely close to mars in the predawn

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sky

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now they were even closer back on august

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9th but still a really pretty spectacle

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this month

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if you're up early and can step outside

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for a look they'll be only a couple of

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degrees apart meaning they'll appear in

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the same field of view

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if you look with most binoculars on

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september 13th and 14th look in the east

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before dawn to see the slim

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crescent moon slip past brilliant venus

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on the 13th you'll find the moon hanging

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above venus with about 20 percent of its

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surface illuminated

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by the next morning the moon has moved

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here to the left of venus

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and has only about 10 percent of its

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sunlit surface visible

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looking toward the south in september

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there's really only

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one relatively bright star for most of

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us who live near cities that star is

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called

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fomalhaut and it's got a pretty

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interesting story the star is about 25

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light years away meaning it's relatively

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close by

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it's also fairly young at just a few

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hundred million years

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and it's still surrounded by a disk of

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debris which is a common feature for

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stars during their planet-forming phase

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now we've discovered thousands of

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exoplanets planets outside our solar

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system

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but fomo heat appeared to be the first

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star to have a planet detected by direct

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imaging with a telescope that being the

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hubble space telescope

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astronomers announced the find back in

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2008

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so fomo out had itself a planet but this

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is where it gets interesting as the

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planet

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had a funky orbit wasn't giving off

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excess heat like a young

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planet should and proceeded to grow

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fainter over the several years that

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followed

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disappearing by 2014 in april 2020

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another team of astronomers using hubble

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announced their finding that fomo hout's

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planet wasn't a planet after all in fact

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their study showed what hubble detected

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was likely a giant expanding cloud of

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debris

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resulting from a huge collision of two

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small bodies made of dust and ice

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similar to worlds you might find in our

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own kuiper belt the scientists calculate

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collisions like this happen around

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fomalhaut only every couple hundred

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thousand years

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so hubble just happened to be looking at

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the right time

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not long after the collision took place

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so we may have lost a planet

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but we gained a cool insight into how

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planetary systems

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form and evolve you can find fomalhaut

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low

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in the south a couple of hours after

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sunset to the left of the bright pair of

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saturn and jupiter

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since it's bright and low in the sky it

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sometimes appears to flicker from

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atmospheric turbulence

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that can cause some skywatchers to

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wonder just what the heck it is

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now you know it's fomalhaut the nearby

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star where it appears we witnessed a

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dramatic planetary collision

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here are the phases of the moon for

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you can catch up on all of nasa's

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missions to explore the solar system and

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beyond at nasa.gov

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i'm preston dykes from nasa's jet

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propulsion laboratory and that's what's