A Celestial Mystery Unveiled!

Exciting revelations from the James Webb Space Telescope (JWST) suggest that two of our solar system's best-known asteroids, Bennu and Ryugu, may actually be fragments of a colossal parent asteroid that was obliterated billions of years ago. This groundbreaking discovery could transform our understanding of how asteroid families are formed and dispersed throughout the cosmos.

Meet the Asteroid Rock Stars!

Bennu, a striking 1,650-foot-wide (500 meters) asteroid, was recently the centerpiece of NASA's OSIRIS-REx mission, which made a successful landing in 2022 and brought samples back to Earth in September 2023, leading to thrilling new finds. On the flip side, Ryugu spans an impressive 2,950 feet (900 meters) and welcomed Japan's Hayabusa2 probe in 2019, which also returned samples in December 2020.

Potential Hazard Alert!

Both asteroids are spinning-top in shape and categorized as "potentially hazardous" due to their size and proximity to our planet. Fortunately, neither poses a significant threat for at least the next century, though NASA is monitoring Bennu closely for a slim collision chance in 2182.

The Family Tree of Space Rocks!

Researchers are investigating the origins of these cosmic companions, with one leading theory positioning them as part of the Polana asteroid family. This intriguing family was born when a massive asteroid shattered in the early solar system. The largest remnant is 142 Polana, a colossal rock over 34 miles (55 kilometers) wide, nestled in the asteroid belt between Mars and Jupiter.

A Comparative Analysis!

In a recent study published on August 18 in The Planetary Science Journal, scientists analyzed spectroscopy data of 142 Polana collected by JWST and compared it with Bennu and Ryugu's samples. Astonishingly, all three asteroids exhibited noticeable similarities, supporting the idea that they originated from the same parent body.

The Collision That Changed Everything!

Study lead author Anicia Arredondo, a planetary scientist at the Southwest Research Institute in Texas, stated, "We believe large asteroids collided early in the solar system's formation, creating an 'asteroid family' with Polana as its largest remnant." The researchers propose that the remnants of this ancient collision gave rise to both Bennu and Ryugu.

Shared Yet Different!

Despite their similarities, subtle differences were noted in the elemental compositions of 142 Polana compared to Bennu and Ryugu. These variations may stem from the asteroids' outer surfaces, which have been influenced by different solar exposures. As Becker noted, "Bennu and Ryugu are much closer to the sun, so their surfaces may be more affected by solar radiation and particles, while Polana has likely withstood micrometeoroid impacts over a longer duration."

A Shared Origin?

While acknowledging the discrepancies, researchers remain convinced that a common ancestor is the most plausible origin for all three asteroids. Arredondo stated, "They are similar enough that we feel confident that all three asteroids could have come from the same parent body." This thrilling possibility not only deepens our cosmic knowledge but also captivates our imagination about the universe's history.