NASA has successfully launched its long-awaited Lucy mission, designed to fly by up to eight Trojan asteroids during its epic journey through the Solar System. Engineers at the agency have also installed a commemorative plaque featuring messages crafted for humanity's descendants.
Trojan asteroids share Jupiter's orbit around the Sun, captured by the planet's gravity. They divide into two groups: the "Trojan camp" at Jupiter's L4 Lagrange point and the "Greek camp" at L5. The Trojans lead Jupiter along its orbital path, while the Greeks trail behind.
Astronomers view these asteroids as primordial relics largely unchanged since the Solar System's formation. To study them up close, NASA developed the Lucy mission in 2017. The spacecraft launched successfully on Saturday, October 16, from Cape Canaveral atop a United Launch Alliance Atlas V 401 rocket.
Lucy's path includes gravity-assist flybys of Earth in 2022 and 2024. It will first visit main-belt asteroid 52246 Donaldjohanson on April 20, 2025, before targeting the L4 Trojan swarm in 2027.
After exploring L4, Lucy returns to Earth for another gravity assist in December 2030, then heads to Jupiter's L5 point. This remarkable odyssey will make Lucy the first spacecraft to visit eight unique destinations in a single mission.
Echoing the iconic Pioneer plaques on Pioneer 10 and 11, Lucy carries a similar artifact with engravings for potential finders. This plaque serves as a lasting testament to the importance of space exploration for humankind's heirs.
Post-mission, the probe will orbit stably between Earth and the Trojans for hundreds of thousands, if not millions, of years. Future generations might one day intercept it and decipher these messages during their own cosmic voyages.
"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", NASA explains in its 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."
Among the engravings are these poignant quotes:
– "When you have seen beyond yourself, then you can see that peace of mind awaits" – George Harrison, legendary Beatles guitarist (d. 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, Muscogee Nation member and U.S. Poet Laureate.
The plaque also includes a diagram depicting planetary positions on Lucy's launch date.
