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pink planet at sunset

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presented by science at nasa

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nasa has recently explored a very

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strange planet

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its days are twice as long as its years

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it has a tail like a comet

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it is capped by deposits of ice

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peppering terrain that elsewhere is hot

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enough to melt lead

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and to top it all off it appears to be

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pink

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the planet is mercury

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of course astronomers have known about

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mercury for thousands of years

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but since nasa's messenger probe went

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into orbit around mercury in 2011

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researchers feel like they've been

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discovering the innermost planet all

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over again

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one finding after another has confirmed

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the alien character of this speedy

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little world which you can see this week

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with your own eyes

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mercury is emerging from the glare of

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the sun for a beautiful two-week

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apparition during the month of february

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2013.

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the show begins about a half hour after

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sunset

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scan the horizon where the sun's glow is

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strongest and if the sky is clear

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mercury should pop out of the twilight

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a bright pink pinprick of light

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mercury itself is not actually pink

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but it is often colored so by the rosy

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hues of the setting sun

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if you're looking on the evening of

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february 8th

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scan the sky around mercury with

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binoculars

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a second planet is there too

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glowing faintly red mars is only a

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fraction of a degree from mercury

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in binocular optics mercury and mars

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form a charming little double planet

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as february unfolds mercury will rise

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higher in the sunset sky brightening as

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it ascends

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from february 11th through 21st the pink

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planet will be visible for as much as an

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hour after sunset

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february 11th is a date of special

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interest

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a slender crescent moon will appear

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straight above mercury providing

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guidance for novice sky watchers

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mercury circles the sun about three

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times closer than earth does

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rotating three times on its axis every

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two mercury years

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this slow spin under the solar inferno

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bakes mercury's surface bone dry and

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raises its daytime temperature to 425

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degrees celsius hot enough to melt lead

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this would seem an unlikely place to

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find deposits of ice

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yet that is what the messenger probe

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recently confirmed

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mercury has enough ice at its poles to

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encase washington dc with a layer of

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frozen water two miles thick

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ice on mercury is possible because the

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tilt of the planet's spin axis is almost

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zero

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less than one degree so there are

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pockets at the planet's poles that never

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see sunlight

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shadowed areas at each end of the

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heavily cratered planet turn out to be

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cold enough to freeze and hold water

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messenger found something else

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much of mercury's ice is coated with a

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mysterious dark substance

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researchers don't know exactly what it

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is

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organic compounds delivered to mercury

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by the impacts of asteroids and comets

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in some ways mercury itself resembles a

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comet with a long tail

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nasa's twin stereo probes on a mission

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to observe the sun

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spotted mercury's tail in 2008

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the messenger probe has flown through it

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the tail appears to be made of material

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blown off mercury's surface by exposure

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to solar flares and the solar wind at

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point-blank range

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with the sun currently approaching the

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maximum of its 11-year activity cycle

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mercury is getting hit by the stormiest

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space weather in years

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this is a great time for messenger to

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study the processes that turn mercury

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into a comet planet

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mercury is a strange planet indeed

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when the sun goes down tonight step

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outside and take a look

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for more news about strange planets in