NASA has just successfully launched its long-awaited Lucy mission which aims to fly by up to eight Trojan asteroids during its journey through the Solar System. On the probe, the engineers of the American agency have also installed a plate on which are drawn several messages intended for the descendants of humanity.
Trojan asteroids are objects that share Jupiter's orbit around the Sun, trapped by the planet's gravitational pull. They fall into two subgroups:the "Trojan camp", located at Jupiter's L4 Lagrange point, and the "Greek camp", located at L5. The former are ahead of Jupiter (in front on the line of orbit), while the latter are placed behind.
Astronomers believe that some of these asteroids could be primordial objects almost unchanged since the formation of the Solar System . To analyze them closely, the agency developed the Lucy mission in 2017. The probe was successfully launched this Saturday, October 16 from the Cape Canaveral base, capped above a United Launch Alliance Atlas V 401 rocket. .
During her journey, Lucy will perform two first gravitational flybys of Earth in 2022 and 2024. The probe will then fly by asteroid 52246 Donaldjohanson, which floats in the main asteroid belt between the orbits of Mars and Jupiter, on April 20, 2025, before reaching its first real targets in 2027, in the L4 swarm that precedes Jupiter.
Lucy will leave the L4 point and return to Earth to take advantage of new gravitational assistance in December 2030, before heading this time to the L5 point of Jupiter. At the end of this incredible journey, Lucy will become the only ship in history to have visited eight different places in a single mission .
The probe will also carry a small plaque similar to the "Pioneer Plaque" attached to the Pioneer 10 and 11 spacecraft on which have been engraved messages and diagrams for further information. potential extraterrestrial civilizations. The Lucy plaque will serve as a reminder of the value of space exploration for the descendants of mankind .
At the end of its mission, the probe will indeed remain in a stable orbit, traveling between Earth and the Trojan asteroids for hundreds of thousands, if not millions years . We could therefore imagine that one day our descendants will be able to "receive" it during their travels in the Solar System and read these few messages.
"This time capsule contains messages from prominent members of our society, individuals who have asked us to contemplate the state of the human condition as well as our place in the universe “, explains NASA in a press release. “These thoughtful leaders have been asked to provide advice, words of wisdom, words of joy, and words of inspiration to those who may read this plaque in the distant future . »
Here are two of the quotes engraved on this plaque.
– “When you have seen beyond yourself, then you can see that peace of mind awaits ". – George Harrison, lead guitarist of the Beatles, who died in 2001.
– “Remember the earth whose skin you are:red earth, black earth, yellow earth, white earth, brown earth, we are the earth ". — Excerpt from Joy Harjo, member of the Muscogee Nation and United States Poet Laureate.
Finally, the plate also features a diagram showing the positions of the planets on the date of Lucy's launch.
