The search for life beyond Earth has led us to explore Mars, probe Jupiter\u2019s moons, and even dream of exoplanets in distant galaxies. But sometimes, the most promising clues lie right here, within our own galaxy\u2026 they may be hidden in icy bodies, dust particles, and ancient rocks that have been floating around since before Earth\u2019s formation. So much so that for decades, scientists have been asking a question that echoes between radio telescopes and space probes: where did the ingredients of life come from?<\/p>\n
Life\u2019s blueprint unveiled: biology\u2019s signal found where no life exists<\/p>\n
To better understand what the scientists found, we need to imagine a chemical compound that, on Earth, is only produced by living organisms. Now, we need to imagine that same compound drifting on an icy comet, with no trace of life nearby. That\u2019s exactly what the scientists discovered\u2026 All of this happened when ESA\u2019s Rosetta probe deliberately collided with comet 67P\/Churyumov-Gerasimenko, located in the constellation Taurus.<\/p>\n
And then, among the dozens of molecules identified by Rosetta, one caught the most attention: dimethyl sulfide (DMS). Here on Earth, it is released by plankton and bacteria. In space, however, its presence suggests something even more fascinating: the chemistry of life can occur even in the absence of life. Remembering that this discovery, made at a temperature of \u2013440 \u00baF (\u2013262 \u00baC), reinforces a hypothesis that is gaining more and more strength: the building blocks of life are universal, and can still arise even in the most inhospitable scenarios.<\/p>\n
Stars burn and ice labs assemble<\/p>\n
Most surprisingly, scientists have already identified more than 200 types of organic compounds in space. Many of them arise through two main processes:<\/p>\n
Stellar smoke: When giant stars die, they release hot, carbon-rich winds. These winds cool, forming PAHs (polycyclic aromatic hydrocarbons), honeycomb-like structures also found in coal, oil, and wood smoke. In fact, this process resembles Earth\u2019s combustion. Literally, stars are burning the ingredients of life.
\nIce labs in the dark: In cold molecular clouds, ice-covered dust grains act as mini-laboratories. There, atoms like hydrogen, carbon, and nitrogen slowly accumulate, forming compounds like:<\/p>\n
Methane
\nMethanol
\nGlycine (the simplest amino acid)<\/p>\n
And then, cosmic radiation breaks these molecules into fragments that recombine into more complex structures.<\/p>\n
\u201cYou can build complexity without much going on in just a cold, dark cloud,\u201d said Alice Booth, an astronomer at Harvard University. In other words, life doesn\u2019t need a planet to begin forming. It starts as chemistry, and this can happen literally in the middle of nowhere (it\u2019s no wonder strange lifeforms bloom near radioactive lakes <\/a>in the U.S.).<\/p>\n Did life spark on Earth \u2014 or did the cosmos deliver its first ingredients?<\/p>\n Now, we must remember that early Earth was hot, hostile, and volcanic. So how did amino acids, the precursors of proteins that gave rise to life, emerge? One of the strongest hypotheses is that these compounds arrived here from space, via comets and asteroids. In fact, some recent evidence includes:<\/p>\n NASA\u2019s OSIRIS-REx mission returned material from the asteroid Bennu, which is rich in organic compounds. All of these discoveries support theories like the \u201cPAH world,\u201d which proposes that Earth\u2019s primordial soup already contained complex compounds from space. Caution is warranted, as compounds like DMS, previously considered biosignatures, are now seen as potential false positives. In other words, not every organic molecule indicates life, but all life requires them. This also reminds us of another recent NASA discovery that detected this \u2018strange\u2019 aquatic, glowing life form<\/a> from space.<\/p>\n","protected":false},"excerpt":{"rendered":"The search for life beyond Earth has led us to explore Mars, probe Jupiter\u2019s moons, and even dream…\n","protected":false},"author":2,"featured_media":100895,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[90,416,56,54,55],"class_list":["post-100894","post","type-post","status-publish","format-standard","has-post-thumbnail","category-space","tag-science","tag-space","tag-uk","tag-united-kingdom","tag-unitedkingdom"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/100894","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=100894"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/100894\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/100895"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=100894"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=100894"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=100894"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nThe asteroid Ryugu, analyzed by the Japanese Hayabusa2 mission, revealed more than 20,000 carbon-based molecules, including 15 types of amino acids.
\nEven the Murchison meteorite, which fell in Australia in 1969, contained 96 distinct amino acids, and life on Earth uses only about 20.<\/p>\n