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[Music]

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what's up for October evenings with

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Giants

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Mars changes course and meteors from

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Orion

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giant planets Jupiter and Saturn are

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visible throughout the night in October

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early in the evening you'll find them to

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the southeast moving slowly Westward

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with the Stars over the course of the

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night they form a triangle with bright

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star formal out when observing the trio

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note how the planets shine with a steady

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light while the star twinkles this can

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be an easy way to know if what you're

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looking at is a planet or a star

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Mars has been steadily working its way

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toward the East all year like it usually

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does relative to the background Stars

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but at the end of October Mars halts

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This apparent motion then appears to

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reverse course

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over the next three months from November

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to late January Mars moves toward the

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west each night then near the end of

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January it reverses direction again and

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continues its Eastward Journey

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this is what's called the retrograde

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motion of Mars it happens about every

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two years and it really threw early

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observers for a loop

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that Mars appears to change its

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direction is an illusion caused by the

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Motions of our planet in its orbit

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passing by the red planet in its orbit

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see Earth and Mars are on these roughly

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circular paths around the Sun like

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Horrors on a racetrack and Earth is on

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the inner faster track

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about every 26 months we overtake Mars

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which is moving slower in its orbit

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during that period when we're passing

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Mars but before we round the bend in our

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orbit to pull away from it we see Mars

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in retrograde appearing to change

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direction even though it's still moving

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forward in its orbit

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so take note of Mars over the next few

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months as it appears to reverse course

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note how its position changes with

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respect to Beetlejuice aldebaran and the

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Pleiades over the weeks and you'll be

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witnessing what was once a source of

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intense curiosity for astronomers but

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which we now know is just a sign of two

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planets passing in the night

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the oriented meteor shower is active

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throughout October and November and

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Peaks on the night of October 20th it's

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a moderate shower usually producing 10

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to 20 meteors per hour at its peak under

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clear Dark Skies this year the moon will

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be about 20 percent full on the peak

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nights so it will interfere a bit when

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it rises a couple of hours before Dawn

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but it shouldn't totally spoil the

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viewing the shower's name comes from the

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fact that you can trace the paths of its

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meteors back to an area on the sky near

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Orion

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these meteors are fragments of dust left

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behind by Comet Halley in a trail that

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extends along its orbit they tend to be

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bright and fast moving and they often

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leave persistent trails that can glow in

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the sky for a few seconds after they

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Streak by no special equipment is needed

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to observe meteor showers just make sure

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you're warm enough and viewing from a

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safe dark spot away from Bright Lights

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then all you have to do is look up and

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enjoy the show

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here are the phases of the moon for

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stay up to date with all of NASA's

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missions to explore the solar system and

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Beyond at nasa.gov I'm Preston Dykes