{"id":801334,"date":"2026-03-25T06:11:29","date_gmt":"2026-03-25T11:11:29","guid":{"rendered":"https:\/\/spaceweekly.com\/?p=801334"},"modified":"2026-03-25T06:11:29","modified_gmt":"2026-03-25T11:11:29","slug":"lifes-genetic-code-just-discovered-in-an-asteroid-sample","status":"publish","type":"post","link":"https:\/\/spaceweekly.com\/?p=801334","title":{"rendered":"Life\u2019s genetic code just discovered in an asteroid sample"},"content":{"rendered":"
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\nThis is a sample of the asteroid Ryugu. The Japanese mission Hayabusa2 brought the sample back to Earth. A new study found all 5 fundamental units of life\u2019s genetic code in this asteroid sample. Image via JAXA.<\/figcaption><\/figure>\n
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Scientists analyzing samples from asteroid Ryugu<\/strong> have detected all five nucleobases used in DNA and RNA.<\/li>\n
The discovery shows that key ingredients for life<\/strong> can form naturally in space. NASA\u2019s mission to asteroid Bennu also yielded all five nucleobases in 2025.<\/li>\n
These compounds may have been delivered to early Earth<\/strong> by meteorites. Did life on Earth get a kickstart from an asteroid? <\/li>\n<\/ul>\n
By Kliti Grice, Curtin University<\/span><\/p>\n
Life\u2019s genetic code discovered in an asteroid\u00a0sample<\/h3>\n
A new study reveals all five fundamental nucleobases \u2013 the molecular letters of life \u2013 have been detected in samples from the asteroid Ryugu.<\/p>\n
Asteroid particles offer a glimpse into the chemical ingredients that may have helped kindle life on Earth. Japan Aerospace Exploration Agency\u2019s (JAXA) Hayabusa2 mission returned the Ryugu samples from space in 2020. <\/p>\n
In 2023, an international team reported they had found one of the nucleobases in these samples: uracil. On March 16, 2026, in a study published in Nature Astronomy<\/em>, a team of Japanese scientists has confirmed all five nucleobases are present in this pristine asteroid material.<\/p>\n
This means these ingredients for life may have been widespread throughout the solar system in its early years.<\/p>\n
Why look for nucleobases?<\/h3>\n
Nucleobases are nitrogen-containing organic molecules. They form the \u201cletters\u201d of genetic information in DNA and RNA. The five main nucleobases are adenine and guanine (known as purines), as well as cytosine, thymine and uracil (known as pyrimidines).<\/p>\n
These molecules combine with sugars and phosphates to yield nucleotides: the building blocks of genetic material. Without nucleobases, the genetic code that allows organisms to grow, reproduce and evolve would not exist.<\/p>\n\n How the 5 nucleobases make up RNA and DNA. Image via Wikimedia Commons, CC BY-SA. <\/figcaption><\/figure>\n
Studying life\u2019s genetic code in Ryugu<\/h3>\n
By studying purines and pyrimidines in Ryugu samples, scientists can reconstruct the chemical history of primitive asteroids. In turn, this gives us a better understanding of how the building blocks of life may have been formed and existed across the solar system.<\/p>\n
Hayabusa2 delivered a total of 5.4 grams of pristine asteroid material. Researchers have to use ultra-clean lab conditions to avoid contaminating it. They extracted organic molecules using water and hydrocholoric acid. Then they purified them for further detection.<\/p>\n
They found all five nucleobases in the two Ryugu samples they analyzed, in roughly similar amounts. <\/p>\n\n Microscope images of Ryugu samples collected from the first and second touchdown sites of the Hayabusa2 mission. Image via JAXA\/ JAMSTEC. <\/figcaption><\/figure>\n
Key components of genetic material \u2026 in space<\/h3>\n
The new results align with previous findings on space rocks. The Murchison meteorite that fell in Australia in 1969 and the Orgueil meteorite in France in 1864 have previously yielded a rich variety of organic molecules, including nucleobases.<\/p>\n
Of course, meteorites that land on Earth can be contaminated by their journey and landing. But pristine samples from NASA\u2019s mission to asteroid Bennu also yielded all five nucleobases in 2025.<\/p>\n
Asteroids such as Ryugu, Bennu, and the parent body of the Orgueil meteorite are remnants of the early Solar System. They can preserve materials largely unchanged for about 4.5 billion years. <\/p>\n
Interestingly, these asteroids show chemical differences. Murchison is enriched in purines, while Bennu and Orgueil contain more pyrimidines. It is thought ammonia may influence this balance. Ammonia is a key molecule that can shape which nucleobases can form.<\/p>\n
By peering into Ryugu\u2019s relatively pristine samples and comparing them with meteorites like Murchison and Orgueil, researchers are tracing the cosmic journey of life\u2019s probable molecular ingredients.<\/p>\n
Their results suggest key components of genetic material may have formed in space and later delivered to the early Earth. In other words, the story of life on our planet may be deeply connected to the chemistry of such ancient asteroids.<\/p>\n\n A colored view of 162173 Ryugu taken by JAXA\u2019s space probe Hayabusa2 in 2018. Image via JAXA\/ Hayabusa2. <\/figcaption><\/figure>\n
A path for the ingredients of life<\/h3>\n
Together, these discoveries show that carbon-rich asteroids throughout the solar system contain diverse prebiotic chemistry. However, the precise mixture of molecules \u2013 such as the balance between purines and pyrimidines \u2013 varies depending on the asteroid\u2019s chemical environment and history.<\/p>\n
Because the Ryugu samples were collected directly in space and protected from Earth\u2019s contamination, they provide one of the clearest views of ancient solar system chemistry.<\/p>\n
The discovery of all five nucleobases on Ryugu suggests the molecular ingredients of life may have been already forming in space billions of years ago. Asteroids may have helped deliver those ingredients to the early Earth \u2026 making the origin of life part of a much larger cosmic chemical story.<\/p>\n
Kliti Grice, John Curtin Distinguished Professor of Organic and Isotope Geochemistry, Curtin University<\/span><\/p>\n
This article is republished from The Conversation under a Creative Commons license. Read the original article.<\/p>\n
Bottom line: Scientists found all 5 fundamental units of life\u2019s genetic code in asteroid Ryugu. It suggests life\u2019s building blocks can form in space and could have been delivered to early Earth.<\/p>\n
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