The recent flyby of the asteroid Donaldjohanson by NASA's Lucy spacecraft on April 20, 2025. This event was indeed celebrated by scientists as it provided the first close-up look at this main belt asteroid. The Lucy mission, which launched in 2021, is on a 12-year journey to study an unprecedented number of asteroids, including those in the Trojan swarms that orbit Jupiter.
Why this could be considered a "Golden Age" of asteroid exploration:
- Multiple Missions: We currently have several active missions dedicated to asteroid exploration:
- Lucy: As mentioned, this mission is conducting flybys of various asteroids to study their diversity and origins. It successfully encountered Dinkinesh in November 2023 and Donaldjohanson in April 2025. Its main targets are the Jupiter Trojan asteroids, with the first encounter scheduled for August 2027.
- OSIRIS-APEX: This is a continuation of the successful OSIRIS-REx mission, which returned a sample from asteroid Bennu in 2023. Now, OSIRIS-APEX is on its way to study asteroid Apophis after its close Earth encounter in 2029.
- Psyche: Launched in 2023, this mission is en route to the unique, metal-rich asteroid Psyche, which it will begin exploring in 2029. Scientists believe Psyche could be the exposed core of an early planet.
- Hayabusa2 (JAXA): While it returned a sample from asteroid Ryugu in 2020, the spacecraft is now on an extended mission, with flybys of asteroids 2001 CC21 (in 2026) and 1998 KY26 (in 2031) planned.
- Diverse Targets: Current missions are targeting a wide range of asteroids, from carbon-rich bodies to metallic ones, and even exploring different populations like the main belt asteroids and the Trojan asteroids. This diversity allows us to learn about the formation and evolution of our solar system.
- Advanced Technology: These missions utilize sophisticated instruments for imaging, spectroscopy, and even sample collection, providing unprecedented data about the composition, structure, and history of asteroids. The success of the DART mission in altering the orbit of Dimorphos also showcased our growing capabilities in planetary defense.
- Sample Return: Missions like OSIRIS-REx and Hayabusa2 have successfully returned samples from asteroids to Earth, allowing for detailed laboratory analysis that can reveal crucial information about the early solar system and the potential building blocks of life.
- Increased Understanding: Each mission and flyby contributes significantly to our understanding of these celestial bodies, helping us to piece together the history of our solar system, assess potential threats from near-Earth asteroids, and even evaluate the resource potential of some asteroids.
The flyby of Donaldjohanson by Lucy is just the latest in a series of exciting events in asteroid exploration, highlighting the ongoing efforts to unlock the secrets these space rocks hold. With more missions planned for the future, this era of discovery is likely to continue for years to come.