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 [Lively music]

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 What's Up for April?

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 Conjunction junction

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 and a hidden surprise
 in the Big Dipper. 

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 At the beginning of April,
 Venus, Mars and Saturn

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 form a trio in the southeast
 before sunrise, with Saturn

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 appearing to move steadily
 toward Mars each day.

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On April 1st, they're a couple
 of finger widths apart.

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 And by the fourth, Saturn

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and Mars are separated by less
than the width of the full moon.

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Saturn then moves on increasing

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 its separation from Mars

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 each day as a new addition to
the morning sky makes its debut.

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 By mid-month,
 Jupiter is starting to rise

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 in the pre-dawn hour.

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Making for a quartet of planets

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 strung out in a line
 across the morning sky.

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 Heading into the last week of
 April, Jupiter will be high

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 enough above the
 horizon in the 

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 before sunrise to make it
 more easily observed.

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 The two brightest
 planets in the sky,

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 Venus and Jupiter, are headed

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 for their own ultra-close
 conjunction on April 30th,

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 similar to the meetup of Mars
and Saturn earlier in the month.

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 In fact, they approach to
 about the same distance.

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 Of course, the planets

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are actually far apart in space

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and only appear to move closer
 or farther apart in the sky

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 as our view of them

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 across the solar system
 changes from month to month.

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 If you recall

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the grand conjunction of Jupiter
and Saturn at the end of 2020,

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 these conjunctions

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are not quite as close as that,

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 but still really impressive

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and they'll make for thrilling
 sights in the morning sky.

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 So definitely try to
 catch them if you can.

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 Whether you call it
 the Big Dipper

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 or Ursa Major or the Plough,

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 it's probably the

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most familiar pattern of bright

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 stars in the northern sky.

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 The Big Dipper
 is a really useful reference

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 for finding your way
 around the sky,

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 but it also contains
 a hidden surprise.

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 One of its stars
 is really two...

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 Or, actually six...

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 Let's break that down.

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 What looks on first glance
 like a single

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bright star here, midway along
 the Dipper's handle, is on

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 closer inspection,
a double star Mizar and Alcor.

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 Next time you have a chance,

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 try to see

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 if you can perceive them
as two stars with your own eyes.

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 Once you give it a try,

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 then grab binoculars
 if you have them,

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 which will easily
 show them as separate stars.

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The two star systems are around

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 a light year apart

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 and are located
 80 light years away

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 from our solar system,
 with Alcor taking

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just shy of a million years to
complete an orbit around Mizar.

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 Now, lots of stars
 are bound together

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 by gravity in small groups,

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especially in pairs or binaries
 that orbit around each other.

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But usually it takes a telescope

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 to be able to see them

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 as separate stars.

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 Mizar and Alcor are a rare
 example of a double star

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 that you can see as a pair

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without the aid of a telescope.

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 But it gets more interesting.

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Although they appear as a close

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 pair of two stars,

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 they are, in fact six.

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 Alcor is a binary
pair of two stars, while Mizar

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 is actually four stars:
 two pairs of binaries.

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 So find the unusual
"double" stars Mizar and Alcor

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 in the Big Dipper in April,
where what at first appears as

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 one star is in reality
 a six-star system.

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 Here are the phases
 of the Moon for April.

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 Stay up to date
 with all of NASA's missions

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 to explore the solar system
 and beyond at NASA.gov.

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I'm Preston Dyches from NASA's
 Jet Propulsion Laboratory

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 and that's
 What's Up for this month.