[Music]
NASA's Lucy mission is heading to the Jupiter Trojans,
two swarms of asteroids trapped in Jupiter's orbit.
When it arrives,
it will provide the first close-up look at these primitive objects,
thought to be fossils from the dawn of the solar system.
But to get there, Lucy needs a little help from the Earth.
[Music]
After launching on October 16th, 2021,
Lucy returned home exactly one year later for the first of three
Earth gravity assists, stealing an undetectably small amount of Earth's
orbital energy to boost the spacecraft.
This allowed Lucy to skim the inner edge of the main asteroid
belt between Mars and Jupiter. On November 1st, 2023,
it flew by asteroid Dinkinesh
and discovered a small moon, which the mission named Selam.
Now, Lucy is returning home once again for another gravitational tug.
On December 12th, at 1:20 p.m.
Eastern Time, it will cross the Moon's orbit from the direction of the Sun,
greeted by a brilliant view of Australia and the Pacific Ocean.
In the hour before closest approach, Lucy will begin to rotate, or slew,
keeping the spacecraft stable as it skims through Earth's upper atmosphere.
Lucy will pick up speed is it approaches the evening terminator,
or boundary between day and night, crossing into Earth's shadow.
At 11:15 p.m., it will make its closest approach to the planet,
skimming about 220 miles above the ocean west of California.
Lucy will be traveling over nine miles per second,
allowing it to streak over North America in only seven minutes.
Just before midnight on the East Coast, Lucy will slew back toward the Sun,
catching a glimpse of sunrise over central Africa.
It will cross the Moon's orbit about half a day later, bidding
farewell to home until its third and final gravity assist in December 2030.
[Music]
The 2024 encounter will boost
Lucy's velocity by four-and-a-half miles per second relative to the Sun,
putting it on course for the L4 Trojans that travel ahead of Jupiter.
But first, Lucy will traverse the main asteroid belt,
making a flyby of asteroid Donaldjohanson on April 20th, 2025.
[Music]