{"id":283999,"date":"2025-11-26T08:11:13","date_gmt":"2025-11-26T08:11:13","guid":{"rendered":"https:\/\/www.newsbeep.com\/uk\/283999\/"},"modified":"2025-11-26T08:11:13","modified_gmt":"2025-11-26T08:11:13","slug":"scientists-reveal-origins-of-giant-object-that-smashed-into-earth-sciencealert","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/uk\/283999\/","title":{"rendered":"Scientists Reveal Origins of Giant Object That Smashed Into Earth : ScienceAlert"},"content":{"rendered":"

One fateful day about 4.5 billion years ago<\/a>, a Mars-sized body called Theia collided with proto-Earth<\/a>, turning both into a molten mess of rock and metal. Once the debris had coalesced, two distinct objects remained locked in an orbit \u2013 Earth and its Moon.<\/p>\n

But where did Theia come from? Right here in the warmer, cozier confines of the inner Solar System, it appears. In fact, Theia and proto-Earth<\/a> may have been neighbors!<\/p>\n

More specifically, Theia may have originated even closer to the Sun than we are today; perhaps closer than most of the material that accreted to form our own baby planet.<\/p>\n

Related: Two Strange Giant ‘Blobs’ Deep Inside Earth May Finally Be Explained<\/a><\/p>\n

These insights come courtesy of a recent study<\/a> led by researchers from the Max Planck Institute for Solar System Research (MPS) and the University of Chicago.<\/p>\n

Researchers analyzed samples from Earth, the Moon<\/a>, and meteorites to check the ratios of numerous isotopes, which are lighter or heavier versions of a certain element with either fewer or additional neutrons in their nucleus.<\/p>\n

\"ReflectiveThin slices of chondrite meteorites showing their namesake chondrules, consisting of small, embedded grains. (Nicole Xike Nie\/Carnegie Science<\/a>)<\/p>\n

“The composition of a body archives its entire history of formation, including its place of origin,” explains<\/a> MPS cosmochemist Thorsten Kleine.<\/p>\n

Given time, materials making up a cooling planet settle in a fashion that depends on differences in their masses, melting points, solubilities, and affinities for other minerals. Iron and zirconium, for example, are found in varying concentrations across Earth’s layers.<\/p>\n

Iron, along with the iron-loving metal molybdenum, would have quickly sunk into the depths of proto-Earth’s core, gathering like the precious jewels sequestered in a medieval dragon’s horde. Zirconium, however, has remained in the mantle during the Earth’s entire existence and has not sunk into the core.<\/p>\n

It stands to reason that much of the iron now found in Earth’s mantle must have arrived after the planet’s reformation; delivered, perhaps, by a world-shattering cosmic impact.<\/p>\n

But where did that iron-carrying object itself come from? Comparing the isotope ratios from different parts of the Solar System allowed the researchers to deduce a potential ‘ingredient list’ for Theia and trace its origin.<\/p>\n

Variations within the giant molecular cloud that formed the Sun and its protoplanetary disk billions of years ago would also have favored the accumulation of different elements and isotopes.<\/p>\n

Like “poorly mixed cake batter<\/a>“, these ratios remained in place, effectively providing a chemical signature for any object born from material in that location.<\/p>\n

\"Win<\/a><\/p>\n

The Moon’s chemical signature of iron, chromium, calcium, titanium, and zirconium matches Earth’s, forcing the researchers to look elsewhere in the Solar System for tell-tale isotope ratios.<\/p>\n

Meteorites<\/a> are location-specific, and due to their primordial state, serve as cosmic time capsules. Those that come from the inner Solar System, or the planet-forming disk, are called non-carbonaceous (NC) meteorites. They’re stony and have had the carbon and other volatile materials baked out of them by their close proximity to the Sun.<\/p>\n

Meteorites from the outer Solar System are called carbonaceous chondrites<\/a> (CC). They formed in more frigid environments, leaving them more carbon-rich, with water still trapped in their interiors.<\/p>\n

Overall, the isotope ratios in the Earth’s mantle match meteorites from the inner Solar System. Yet the isotopes the researchers assigned to Theia “have ratios that were previously unknown<\/a> and do not match the building blocks of Earth.”<\/p>\n

“The most convincing scenario is that most of the building blocks of Earth and Theia originated in the inner Solar System,” concludes<\/a> lead-author and MPS geoscientist, Timo Hopp.<\/p>\n

“Earth and Theia are likely to have been neighbors.”<\/p>\n

The rest, as is said, is history: the momentous clash between neighbors gave us our Moon, which has been drifting away<\/a> ever since and is currently distancing itself from Earth at a sloth-like rate of 1.5 inches (3.8 centimeters) per year.<\/p>\n

This research is published in the journal Science<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"One fateful day about 4.5 billion years ago, a Mars-sized body called Theia collided with proto-Earth, turning both…\n","protected":false},"author":2,"featured_media":284000,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[249,90,416,56,54,55],"class_list":{"0":"post-283999","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-space","8":"tag-msft-content","9":"tag-science","10":"tag-space","11":"tag-uk","12":"tag-united-kingdom","13":"tag-unitedkingdom"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/283999","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=283999"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/283999\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/284000"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=283999"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=283999"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=283999"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}