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♪

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>> [Narrator] How do we
navigate through space?

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Currently, spacecraft
flying beyond Earth

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don’t have a GPS to find
their way through space.

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Navigators on Earth send a
signal to the spacecraft,

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which receives it
and sends it back.

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Extremely precise clocks on the
ground, called atomic clocks,

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measure how long it
takes the signal

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to make this two-way journey.

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The amount of time tells them
how far away the spacecraft is,

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and how fast it’s going.

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The farther out in space
the spacecraft is,

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the longer it takes to
receive and send a signal.

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But what if humans are sent
to another planet like Mars?

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A two-way system

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that sends a signal from
Earth to a spacecraft,

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back to Earth and then to
the spacecraft again

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would take an average
of 40 minutes.

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Imagine if the GPS
on your phone

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took 40 minutes to
calculate your position.

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You might miss your turn, or be
several exits down the highway

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before it caught up with you.

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If humans travel to
the Red Planet,

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it would be better if the
system was one-way,

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allowing the explorers
to immediately

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determine their current position
rather than waiting

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for that information to
come back from Earth.

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NASA is testing new technology

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that would allow future
explorers to do just that.

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The Deep Space Atomic Clock is
the first demonstration of an

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atomic clock that can be used
for navigation in deep space.

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It will allow a spacecraft to
calculate its own trajectory,

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instead of depending on Earth.

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If a spacecraft had one of
these clocks on board,

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it could receive a
signal from one of those

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big antennas on Earth,

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and quickly measure its
speed and position.

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The Deep Space Atomic Clock
could one day let astronauts

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navigate safely and
accurately to Mars and beyond.

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This technology demonstration is
the first step in making one-way

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space navigation a reality.

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[Explore Space Tech]

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[NASA]