In 2023, an international team reported<\/a> they had found one of the nucleobases in these samples \u2013 uracil. Now, in a study published in Nature Astronomy today<\/a>, 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?<\/p>\n Nucleobases are nitrogen-containing organic molecules that 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 \u2013 the building blocks of genetic material. Without nucleobases, the genetic code that allows organisms to grow, reproduce and evolve would not exist.<\/p>\n How the five nucleobases make up RNA and DNA. 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<\/a> of pristine asteroid material. Researchers have to use ultra-clean lab conditions<\/a> to avoid contaminating it. They extracted organic molecules using water and hydrocholoric acid, and then purified them for further detection.<\/p>\n They found all five nucleobases in the two Ryugu samples they analysed, in roughly similar amounts. <\/p>\n Microscope images of Ryugu samples collected from the first and second touchdown sites of the Hayabusa2 mission. Key components of genetic material \u2013 in space<\/p>\n The new results align with previous findings on space rocks. The Murchison meteorite that fell in Australia in 1969<\/a>, and the Orgueil meteorite in France, 1864<\/a>, 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<\/a> 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 this balance may be influenced by ammonia, 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![\"\"](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/03\/file-20260312-57-n1u0vh.jpg\")
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