Ongoing efforts to decipher the chemical composition of the asteroid sample have revealed the purest collection of organic molecules, supporting theories suggesting that biology has its roots in space.
And for more than two years now, material from the surface of the asteroid Ryugu has been delivered to Earth in a sealed capsule. Since then, researchers from around the world have worked together to study its composition to better understand how it correlates with the evolution of our solar system.
These latest discoveries highlight the connection between the carbon-based compounds found in chondrites and the chemical composition of the asteroids they originated from.
And by looking at the similarities and differences between Ryugu specimens and carbonaceous chondrite meteorites on Earth, scientists can take a fresh look at the meteorites in our collections. In other words, samples of real asteroids are useful for confirming hypotheses based on their parts reaching the surface of our planet shortly after passing through the atmosphere.
“Previous analyzes have identified organic molecules in carbonaceous chondrites, but so far we have not been able to tell whether these primordial emissions are different from those found on asteroids or not. Our work with Ryugu samples provides the first direct link between organic matter in chondrites and asteroids.”
Often referred to as the building blocks of life because of the role they play in the origin of life, the newly identified molecules include several types of amino acids that combine to create the proteins on which organisms depend.
In just 5 grams (0.18 oz) of material, about 20,000 organic molecules have been identified. These include organic compounds such as carboxylic acids, amines and aromatic hydrocarbons; Compounds that are closely related to a wide range of important molecules throughout the living world.
The results support the idea that the ingredients necessary for the origin of life came to our planet in a very complex form as a result of asteroid impacts. How this organic dust could evolve into some sort of advanced chemistry remains a matter of debate, but knowing that space provides the right conditions for many related compounds to form gives scientists a good start to experiment.
Since these asteroids are essentially leftovers from when the solar system formed about 4.5 billion years ago, they can also tell us a lot about the early moments of our planet’s formation.
With the help of certain chemical determinants, including the amount of water, scientists can try to determine when and where Ryugu formed, giving us a snapshot of conditions at a particular stage in the evolution of the solar system.
“At least some of the organic material in the Ryugu samples predates the formation of the Sun and formed under very cold conditions,” says geochemist George Cody of the Carnegie Institution of Science in Washington, DC.
These new studies show the usefulness of probes that collect material from asteroids, such as the Hayabusa 2 spacecraft that recovered rocks from Ryugu. And, unlike the meteorite samples, this dust and rock has not been affected by any weathering factors as it is exposed to soil, water and air.
What’s more, trying to analyze an asteroid in space is also difficult – not least because it moves very fast and reflects little light, which limits the readings that instruments can get. In the lab, more time and attention can be devoted to extracting data from these materials.
“In the past, our research was limited to studying space rocks that came to us as a result of a collision with the Earth,” says Cody. .”
Both articles were published in the journal Science.
Source: Science Alert