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[Music]

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NASA’s Lucy mission is heading
to the Jupiter Trojans

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two swarms of primitive
asteroids trapped in Jupiter’s

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orbit that may hold clues to the
formation of the planets.

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Lucy launched on October 16,
2021.

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After a year in orbit around
the Sun,

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it is returning home on its
launch anniversary

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for the first of three Earth
gravity assists.

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On October 16, 2022, Lucy will
fly by the Earth

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like a partner in a swing dance,
boosting its speed

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and elongating its orbit
around the Sun.

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Two years later, it will return
for a second gravitational

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tango to lengthen its orbit even
further, allowing it to reach

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the L4 Trojan asteroids that
travel ahead of Jupiter.

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After Lucy completes its first
tour of the Trojans,

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it will make its third pas de
deux with Earth

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in December 2030.

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This final flyby will increase
its orbital tilt

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and bend its path toward
the L5 Trojans

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that follow Jupiter.

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As Lucy approaches its first
gravity assist,

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it will use the Earth
and the Moon

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to calibrate its instruments.

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A day before it arrives, NASA
will begin scanning

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for potential collisions.

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Lucy’s path runs through a
cloud of over six thousand

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Earth-orbiting satellites, and
about twenty times as many

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bits of inactive debris.

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If any potential collisions are
detected, the spacecraft will

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fire its thrusters to speed up
its arrival by a few seconds,

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avoiding a catastrophic impact.

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Because Lucy will approach
from Earth’s dayside,

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it will initially be invisible
to observers on the ground.

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It will take pictures of the
Eastern Hemisphere

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and attempt to image Ethiopia,
home of the famous

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hominin fossil for which the
mission is named.

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Lucy will then pick up speed as
it races toward the

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evening terminator, or boundary
between day and night.

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It will emerge from the Sun’s
glare as night falls

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on Western Australia – with its
expansive solar arrays

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reflecting the daylight.

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An hour after sunset, at 6:55pm,
Western Australia time,

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stargazers will be treated to a
magnificent sight

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as Lucy streaks across the sky.

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Seven minutes later, Lucy
will once again

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slip from view as it
crosses into the

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shadow of the Earth.

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At 7:04 pm, Lucy will make its
closest approach at just

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219 miles above the planet:
lower than the

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International Space Station.

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This exceptionally close shave
will increase its velocity

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by four-and-a-half miles
per second.

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Lucy will traverse the night
side of Earth,

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rapidly gaining in altitude, and
emerge from the planet’s shadow

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at 4:26 am, Pacific Time.

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If skies are clear, early birds
in the Western US

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will be able to spot the
spacecraft through binoculars.

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Lucy will appear in the
southwestern sky

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between Cetus and Pisces, rising
eastward until it is

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overtaken by the dawn.

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As the Sun rises over the
Rocky Mountains,

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Lucy will speed away from
Earth at more than

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14.000 miles per hour.

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crossing the lunar orbit in
less than a day.

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Lucy will take a few
final images as it

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approaches the Moon and
bids farewell to home,

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preparing for over two years
in deep space,

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until it returns for its second
gravity assist in December 2024.

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[Music]