Ryugu: An asteroid that occasionally approaches Earth.
Credit: JAXA
Recent discoveries from samples collected from the asteroid Ryugu indicate that all five key components of DNA and RNA have been identified. This finding substantiates the theory that asteroids could have played a crucial role in delivering the fundamental building blocks of life to Earth billions of years ago.
In 2018, Japan’s Hayabusa2 spacecraft successfully visited Ryugu, employing two projectiles—one large and one small—to gather samples from the asteroid’s surface. After returning to Earth with these samples in 2020, scientific analysis has been ongoing.
Dr. Yasuhiro Ohba and a team of researchers from Hokkaido University analyzed two distinct samples from Ryugu: surface material and subsurface material obtained from the excavation caused by the projectile. The findings revealed all five major nucleobases, which are essential components that pair with sugars and phosphates to create nucleic acids, including DNA and RNA.
This isn’t the first instance of nucleobases being detected in asteroid samples; they have also been found in meteorities and samples from the asteroid Bennu. However, researchers observed variability in the abundance of nucleobases across different samples, pointing toward the potential to trace asteroids and meteorites back to their original celestial bodies, thus unraveling their evolutionary history.
The detection of nucleobases in samples from Ryugu and other asteroids highlights their potential significance in the history of life on Earth. “Their presence in Ryugu reinforces their prevalence throughout the solar system,” states Ohba. If these asteroids are indeed abundant in the precursors of DNA, they may have been instrumental in the emergence of life on our planet.
Furthermore, Ryugu and similar asteroids might harbor even more complex organic molecules, including nucleic acids. “Complex organic compounds like DNA and RNA are likely to form in asteroids,” notes Ohba, underscoring their critical role in the origin of life on Earth.
Topics:
- Asteroid/
- Extraterrestrial Life
Source: www.newscientist.com
