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[Music]

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what's up for april

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morning planets a sunset arch and

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finding leo the lion

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the morning sky on april 6th finds

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jupiter and saturn forming a lovely trio

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with the crescent moon

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look for them low in the southeast in

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the hour before sunrise

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april 22nd is earth day an annual

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opportunity to collectively appreciate

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the wonder and beauty of our home planet

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so it seems appropriate to feature an

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earth-related site you can see

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any time of the year when you have clear

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skies it's a twilight phenomenon that

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you might have noticed

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just after sunset if you can pull your

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gaze away from the sunset in the west

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and spin yourself around to

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face east you'll often notice a band of

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pink or orange colored sky with a darker

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bluish band underneath

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these bands move upward over the minutes

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following sunset to form an arch across

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the sky that slowly fades as night sets

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in

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above it the rosy hued band is known as

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the belt

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of venus we observe this site for a

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short time after sunset when the sun is

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just below the horizon

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but some of its light rays are still

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making their way through the atmosphere

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before nightfall

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the redder or longer wavelengths of

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sunlight are able to travel the longest

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distance through the atmosphere

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and at the point opposite to the sunset

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this reddish light is scattered off the

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atmosphere and back toward your eyes

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the belt of venus is named not for the

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planet but for the mythical goddess

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together with earth's shadow these

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sights form the anti-twilight arch

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this arch rises like a curtain on the

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night slowly fading as earth's shadow

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eventually fills the sky

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allowing us to gaze outward into the

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stars you can see this sight in morning

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twilight as well by looking in the

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direction opposite the rising sun

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that is toward the west as the sky

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begins to lighten

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earth's shadow becomes noticeable with

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the belt of venus above it

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and these bands slowly sink to the

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april is a great time to look for leo

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that is the constellation

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leo leo is the latin word for lion

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and this well-known grouping of stars is

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named for a super-powered lion

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vanquished by the mythical hero hercules

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it's a pretty easy constellation to

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locate because it sort of looks like a

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lion reclining in the sky and has this

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recognizable curving shape called the

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sickle that represents the lion's head

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in april you can find leo high overhead

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in the south in the first few hours

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after sunset

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in addition to the sickle shape of the

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lion's head look for the lion's

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heart the brilliant bluish-white star

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regulus which is one of the brightest

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stars in the sky

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astronomers think most stars have a

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family of planets orbiting them

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and these two bright stars in leo named

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algiba which is actually a double star

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and raceless each have a confirmed

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planet larger than jupiter orbiting

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around them

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so step out after dark in april to look

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for leo with its sickle-shaped lion's

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mane

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and blazing bluish heart

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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