All the key components of the genetic code have been found in the asteroid

These are the so-called nucleobases, the molecules that form the genetic information.

These include:

• adenine
• guanine
• cytosine
• thymine
• uracil

These are the building blocks of DNA and RNA, the systems that allow living organisms to store and transmit information.

Details

Scientists have found all five of these molecules in samples from the asteroid Ryugu.

These samples:

• were delivered to Earth in 2020
• collected by the Hayabusa2 mission
• are considered to be virtually uncontaminated by terrestrial matter

This makes the results particularly reliable.

Why it's important

Previously, individual components of the genetic code have been found in space objects.

Now, for the first time, it's been confirmed that all the basic molecules are present at the same time.

This means that such matter could have formed:

• not only on Earth
• but also in space

The scientists emphasise that this is not about life itself.

But the results suggest that

• "the building blocks of life could have come from outer space
• asteroids could have brought them to Earth

This makes the origin of life part of a wider cosmic chemistry.

The research also shows that the composition of such molecules can vary from asteroid to asteroid.

It depends on:

• chemical conditions
• the presence of substances such as ammonia

The discovery is important for understanding

• how the first molecules of life might have arisen
• how asteroids might have played a role
• how common such substances are in the Universe

Background

The samples from asteroid Ryugu were delivered by Japan's Hayabusa2 mission. They are considered to be some of the "cleanest" materials from the early solar system.

Source

The study is published in the journal Nature Astronomy.