NASA Launches Lucy!

~3 min

NASA is ready to launch its Lucy mission that will help scientists understand how the Solar System planets formed. Today, we’ll tell you everything you need to know about this remarkable mission.

What is Lucy?

Lucy is NASA’s space probe that will become the first to study Jupiter’s Trojan asteroids. The mission will last for 12 years, during which Lucy will explore seven different targets: one main-belt asteroid and six Trojans. No other spacecraft in history has managed to visit that many asteroids during one mission.

On its 12-year journey, Lucy will travel almost 6.5 billion km (4 billion miles) and make three and a half loops around the Sun. The spacecraft’s average speed will be about 63,000 km/h (39,000 mph); when Lucy passes each of the asteroids, it will be moving at a speed of 24,000 km/h (15,000 mph).

What are the Trojan asteroids?

Trojans are any asteroids in the orbit of a planet or large moon that remain near one of its Lagrange points – L4 and L5. Most known Trojan asteroids share the orbit of Jupiter. They are divided into two large groups: the Greek camp at L4 and the Trojan camp at L5.

Why are Jupiter’s Trojans important for scientists? The Trojan asteroids are leftovers from the very early days of the Solar System – they existed even before the planets were formed. While many other primordial space rocks were scattered into the distant regions of the Solar System and beyond, the Trojans were captured by Jupiter, which our spacecraft are capable of reaching. If we study these asteroids, we will be able to learn more about the history of the Solar System and maybe the origins of organic materials on the Earth.

Lucy mission targets

In 2025, before visiting the Trojans, Lucy will fly by the main-belt asteroid 52246 Donaldjohanson. This small asteroid will primarily serve as a test object for the spacecraft’s scientific equipment.

In 2027, Lucy will reach the Greek camp of Jupiter’s Trojans at L4. There, it will visit four Trojan asteroids: 3548 Eurybates, 15094 Polymele, 11351 Leucus, and 21900 Orus.

After that, Lucy will head back to the Earth to receive a gravity assist, and then start its journey to the Trojan camp at L5. In 2033, the spacecraft will fly by the binary pair of asteroids: 617 Patroclus and its companion Menoetius.

You can see animations and a diagram showing all Lucy’s flybys on the mission's official website.

What will Lucy study?

Lucy is equipped with high-resolution cameras, an infrared spectrometer, and a thermal spectrometer. These scientific instruments will help collect data on the asteroids’ surface geology, sub-surface composition, mass, density, and other properties. Lucy will also look for satellites and rings that some of the Trojan asteroids might have.

Lucy launch date

Lucy lifted off on October 16, 2021, from Space Launch Complex 41 at Cape Canaveral Space Force Station (Florida, USA). The spacecraft was carried by a United Launch Alliance Atlas V rocket.

Interesting facts

  • The spacecraft Lucy was named after the fossilized skeleton of Australopithecus afarensis discovered in 1974. The skeleton Lucy, in turn, was named after the Beatles’ song “Lucy in the Sky with Diamonds”.
  • The first asteroid that Lucy will visit – 52246 Donaldjohanson – was named after one of the discoverers of the Lucy fossil.
  • After studying the Trojans at Jupiter’s L4, Lucy will come back to the Earth to receive a gravity assist. Thus, it will become the first spacecraft to return to the Earth’s vicinity from the outer Solar System.
  • Lucy carries a plaque containing information for our descendants. It includes the spacecraft’s launch date, the positions of the planets at the launch date, and quotes from famous people such as Albert Einstein, Carl Sagan, and John Lennon.

Let’s hope that Lucy successfully gets to Jupiter’s Trojans and provides us with some new exciting facts about the history of the Solar System. Good luck, Lucy!