{"id":9414,"date":"2024-10-21T17:25:00","date_gmt":"2024-10-21T21:25:00","guid":{"rendered":"https:\/\/spaceandplanetarynewswire.com\/?p=9414"},"modified":"2024-10-21T17:25:00","modified_gmt":"2024-10-21T21:25:00","slug":"what-happened-when-a-meteorite-the-size-of-four-mount-everests-hit-earth","status":"publish","type":"post","link":"https:\/\/spaceandplanetarynewswire.com\/?p=9414","title":{"rendered":"What Happened When a Meteorite the Size of Four Mount Everests Hit Earth?"},"content":{"rendered":"
Graphical depiction of the S2 impact and its immediate aftereffects.<\/figcaption><\/figure>\n

Billions of years ago, long before anything resembling life as we know it existed, meteorites frequently pummeled the planet. One such space rock crashed down about 3.26 billion years ago, and even today, it\u2019s revealing secrets about Earth\u2019s past.    <\/p>\n

Nadja Drabon<\/a>, an early-Earth geologist and assistant professor in the Department of Earth and Planetary Sciences<\/a>, is insatiably curious about what our planet was like during ancient eons rife with meteoritic bombardment, when only single-celled bacteria and archaea reigned \u2013 and when it all started to change. When did the first oceans appear? What about continents? Plate tectonics? How did all those violent impacts affect the evolution of life?<\/p>\n

A new study in Proceedings of the National Academy of Sciences<\/em> sheds light on some of these questions, in relation to the inauspiciously named \u201cS2\u201d meteoritic impact of over 3 billion years ago, and for which geological evidence is found in the Barberton Greenstone<\/a> belt of South Africa today. Through the painstaking work of collecting and examining rock samples centimeters apart and analyzing the sedimentology, geochemistry, and carbon isotope compositions they leave behind, Drabon\u2019s team paints the most compelling picture to date of what happened the day a meteorite the size of four Mount Everests paid Earth a visit.<\/p>\n

\u201cPicture yourself standing off the coast of Cape Cod, in a shelf of shallow water. It\u2019s a low-energy environment, without strong currents. Then all of a sudden, you have a giant tsunami, sweeping by and ripping up the sea floor,\u201d said Drabon.<\/p>\n

Drabon with students David Madrigal Trejo and \u00d6yk\u00fc Mete during fieldwork in South Africa. Photo courtesy of Nadja Drabon<\/figcaption><\/figure>\n

The S2 meteorite, estimated to have been up to 200 times larger than the one that killed the dinosaurs, triggered a tsunami that mixed up the ocean and flushed debris from the land into coastal areas. Heat from the impact caused the topmost layer of the ocean to boil off, while also heating the atmosphere. A thick cloud of dust blanketed everything, shutting down any photosynthetic activity taking place.<\/p>\n

But bacteria are hardy, and following impact, according to the team\u2019s analysis, bacterial life bounced back quickly. With this came sharp spikes in populations of unicellular organisms that feed off the elements phosphorus and iron. Iron was likely stirred up from the deep ocean into shallow waters by the aforementioned tsunami, and phosphorus was delivered to Earth by the meteorite itself and from an increase of weathering and erosion on land.<\/p>\n

Drabon\u2019s analysis shows that iron-metabolizing bacteria would thus have flourished in the immediate aftermath of the impact. This shift toward iron-favoring bacteria, however short-lived, is a key puzzle piece depicting early life on Earth. According to Drabon\u2019s study, meteorite impact events \u2013 while reputed to kill everything in their wake (including, 66 million years ago, the dinosaurs) \u2013 carried a silver lining for life. <\/p>\n

\u201cWe think of impact events as being disastrous for life,\u201d Drabon said. \u201cBut what this study is highlighting is that these impacts would have had benefits to life, especially early on \u2026 these impacts might have actually allowed life to flourish.\u201d<\/p>\n

These results are drawn from the backbreaking work of geologists like Drabon and her students, hiking into mountain passes that contain the sedimentary evidence of early sprays of rock that embedded themselves into the ground and became preserved over time in the Earth\u2019s crust. Chemical signatures hidden in thin layers rock help Drabon and her students piece together evidence of tsunamis and other cataclysmic events.<\/p>\n

The Barberton Greenstone Belt in South Africa, where Drabon concentrates most of her current work, contains evidence of at least eight impact events including the S2. She and her team plan to study the area further to probe even deeper into Earth and its meteorite-enabled history.<\/p>\n","protected":false},"excerpt":{"rendered":"

Billions of years ago, long before anything resembling life as we know it existed, meteorites frequently pummeled the planet. One such space rock crashed down about 3.26 billion years ago, and even today, it\u2019s revealing secrets about Earth\u2019s past.     Nadja Drabon, an early-Earth geologist and assistant professor in the Department of Earth and Planetary Sciences,…<\/p>\n","protected":false},"author":71,"featured_media":9416,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"fifu_image_url":"https:\/\/news.harvard.edu\/wp-content\/uploads\/2024\/10\/meteorite_impact35.jpg","fifu_image_alt":"","footnotes":""},"categories":[213],"tags":[],"class_list":["post-9414","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-impact"],"_links":{"self":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/9414","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/users\/71"}],"replies":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=9414"}],"version-history":[{"count":1,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/9414\/revisions"}],"predecessor-version":[{"id":9417,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/posts\/9414\/revisions\/9417"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=\/wp\/v2\/media\/9416"}],"wp:attachment":[{"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=9414"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=9414"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/spaceandplanetarynewswire.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=9414"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}