Lucy's Asteroid Grand Tour

Early Saturday morning, if all goes to plan, a mission spanning the course of twelve years will take flight to explore some of our solar system’s most ancient objects. The mission in question is Lucy, named after the 3.2 million year old hominin skeleton discovered in 1974. This archeological discovery gave us an unprecedented look into our early ancestors, advancing our theories of evolution. Correspondingly, the Lucy mission aims to dramatically expand humanity’s knowledge of our solar system, providing insights into its primordial development.

The Lucy spacecraft has a mass of approximately 1,500 kilograms, and with its massive solar panels unfurled it has a length of over 14 meters (~46 ft), which is around the size of a city bus! The spacecraft’s instrument platform contains three primary remote-sensing devices: L’TES (Lucy Thermal Emission Spectrometer), L’LORRI (Lucy Long Range Reconnaissance Imager), and L’Ralph which is a Multi-spectral Visible Imaging Camera (MVIC). These instruments will allow NASA to gather detailed information on eight different asteroids.

The mission will be carried to space by an Atlas V-401, a variant of the Atlas V rocket family which has no solid-rocket boosters and an upper stage with one engine. It will launch from SLC-41 (Space Launch Complex 41), a launch site which has a rich history of supporting interplanetary missions. Once the spacecraft is placed into its initial heliocentric orbit, it will need to complete a series of gravity assists around the Earth to reach all eight asteroids. This will take many years to complete, yet the results should be well worth the wait.

Of the asteroids which will be visited, one is classified as a Main Belt asteroid and the other seven are Trojan asteroids – located within two of Jupiter’s Lagrange points (L4 & L5). These Lagrange points are stable zones in space formed through the gravitational interaction between Jupiter and the Sun. The left over “building blocks” of the solar system collected in these stable zones and were persevered for billions of years, and now we will send a spacecraft hundreds of millions of miles away to reveal some of their secrets!