{"id":136343,"date":"2024-12-12T23:01:09","date_gmt":"2024-12-12T16:01:09","guid":{"rendered":"https:\/\/hotvideos24.online\/?p=136343"},"modified":"2024-12-12T23:01:09","modified_gmt":"2024-12-12T16:01:09","slug":"comets-played-a-major-role-in-making-life-on-earth-possible-new-study-hints","status":"publish","type":"post","link":"https:\/\/hotvideos24.online\/?p=136343","title":{"rendered":"Comets played a &#8216;major&#8217; role in making life on Earth possible, new study hints"},"content":{"rendered":"<p> <script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-3711241968723425\"\r\n     crossorigin=\"anonymous\"><\/script>\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block\"\r\n     data-ad-format=\"fluid\"\r\n     data-ad-layout-key=\"-fb+5w+4e-db+86\"\r\n     data-ad-client=\"ca-pub-3711241968723425\"\r\n     data-ad-slot=\"7910942971\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><br \/>\n<\/p>\n<div itemprop=\"articleBody\" id=\"article-body\">\n<p>The idea that comets delivered water to early Earth has fallen out of favor in the past decade, but a new look at data from the <a data-analytics-id=\"inline-link\" href=\"https:\/\/www.livescience.com\/tag\/european-space-agency\" data-auto-tag-linker=\"true\" data-before-rewrite-localise=\"https:\/\/www.livescience.com\/tag\/european-space-agency\">European Space Agency<\/a>&#8216;s (ESA) Rosetta mission to an iconic \u201crubber ducky\u201d comet has reopened that possibility.<\/p>\n<p>Water has a pretty simple chemical makeup: just three atoms (two hydrogen and one oxygen) in each molecule. It&#8217;s also one of Earth&#8217;s most abundant molecules, with our planet&#8217;s oceans brimming with about a million trillion tons of the liquid.<\/p>\n<aside class=\"hawk-nest\" data-block-type=\"embed\" data-render-type=\"fte\" data-skip=\"dealsy\" data-widget-type=\"seasonal\"\/>\n<p>How all of this <a data-analytics-id=\"inline-link\" href=\"https:\/\/www.livescience.com\/52332-why-is-water-needed-for-life.html\" data-before-rewrite-localise=\"https:\/\/www.livescience.com\/52332-why-is-water-needed-for-life.html\"><u>water<\/u><\/a> ended up on Earth, though, has remained a mystery. Some scientists think that although Earth&#8217;s geological processes may have generated a tiny fraction of it, most water was likely deposited by <a data-analytics-id=\"inline-link\" href=\"https:\/\/www.livescience.com\/space\/astronomy\/comets\" data-before-rewrite-localise=\"https:\/\/www.livescience.com\/space\/astronomy\/comets\"><u>comets<\/u><\/a> or <a data-analytics-id=\"inline-link\" href=\"https:\/\/www.livescience.com\/space\/astronomy\/asteroids\" data-before-rewrite-localise=\"https:\/\/www.livescience.com\/space\/astronomy\/asteroids\"><u>asteroids<\/u><\/a> via repeated, cataclysmic collisions.<\/p>\n<p>Figuring out which of these two groups was responsible involves a special chemical signature that arises because the hydrogen in water occurs in two distinct isotopes, or forms. Whereas most hydrogen atoms contain just one proton in their nucleus, a tiny fraction harbors an additional neutron. The chemical signature involves measuring the amount of this heavier hydrogen isotope, called deuterium, relative to its lighter, regular form \u2014 a quantity called the deuterium-to-hydrogen ratio, or D\/H.<\/p>\n<p>&#8220;The D\/H in water tells us at what temperature the ice formed, and from that how far a comet formed from the Sun,&#8221; <a data-analytics-id=\"inline-link\" href=\"https:\/\/science.nasa.gov\/people\/kathleen-mandt\/\" target=\"_blank\" data-url=\"https:\/\/science.nasa.gov\/people\/kathleen-mandt\/\" referrerpolicy=\"no-referrer-when-downgrade\" data-hl-processed=\"none\" rel=\"noopener\"><u>Kathleen Mandt<\/u><\/a>, a planetary scientist at <a data-analytics-id=\"inline-link\" href=\"https:\/\/www.livescience.com\/tag\/nasa\" data-auto-tag-linker=\"true\" data-before-rewrite-localise=\"https:\/\/www.livescience.com\/tag\/nasa\">NASA<\/a> and corresponding author of a new study describing the reanalysis, told Live Science in an email. The lower the D\/H value is, the farther from the <a data-analytics-id=\"inline-link\" href=\"https:\/\/www.livescience.com\/what-is-the-sun\" data-before-rewrite-localise=\"https:\/\/www.livescience.com\/what-is-the-sun\"><u>sun<\/u><\/a> the asteroid or comet was born.<\/p>\n<p><strong>Related: <\/strong><a data-analytics-id=\"inline-link\" href=\"https:\/\/www.livescience.com\/space\/comets\/crumb-trails-of-meteoroids-could-reveal-potential-planet-killer-comets-years-before-they-reach-earth\" data-before-rewrite-localise=\"https:\/\/www.livescience.com\/space\/comets\/crumb-trails-of-meteoroids-could-reveal-potential-planet-killer-comets-years-before-they-reach-earth\"><u><strong>&#8216;Crumb trails&#8217; of meteoroids could reveal potential &#8216;planet-killer&#8217; comets years before they reach Earth<\/strong><\/u><\/a><\/p>\n<p>Research over the past few decades has shown that Earth&#8217;s D\/H ratio is similar to those of many asteroids and a handful of <a data-analytics-id=\"inline-link\" href=\"https:\/\/astronomy.swin.edu.au\/cosmos\/J\/Jupiter-family+comets\" target=\"_blank\" data-url=\"https:\/\/astronomy.swin.edu.au\/cosmos\/J\/Jupiter-family+comets\" referrerpolicy=\"no-referrer-when-downgrade\" data-hl-processed=\"none\" rel=\"noopener\"><u>Jupiter-family comets<\/u><\/a> \u2014 a group of comets that swing past the sun roughly every 20 years and whose paths are tweaked by Jupiter&#8217;s gravity.<\/p>\n<div id=\"slice-container-newsletterForm-articleInbodyContent-YMHSesHGUQ7qZxY85mY9D7\" class=\"slice-container newsletter-inbodyContent-slice newsletterForm-articleInbodyContent-YMHSesHGUQ7qZxY85mY9D7 slice-container-newsletterForm\">\n<div data-hydrate=\"true\" class=\"newsletter-form__wrapper newsletter-form__wrapper--inbodyContent\">\n<div class=\"newsletter-form__container\">\n<section class=\"newsletter-form__top-bar\"\/>\n<section class=\"newsletter-form__main-section\">\n<p class=\"newsletter-form__strapline\">Get the world\u2019s most fascinating discoveries delivered straight to your inbox.<\/p>\n<\/section>\n<\/div>\n<\/div>\n<\/div>\n<p>But the D\/H value of the &#8220;rubber ducky&#8221; comet 67P\/Churyumov-Gerasimenko, determined in a 2015 study, essentially ended the case for comets. Averaged over 150 measurements collected by ESA&#8217;s <a data-analytics-id=\"inline-link\" href=\"https:\/\/www.space.com\/24292-rosetta-spacecraft.html\" target=\"_blank\" data-url=\"https:\/\/www.space.com\/24292-rosetta-spacecraft.html\" referrerpolicy=\"no-referrer-when-downgrade\" data-hl-processed=\"none\" rel=\"noopener\"><u>Rosetta mission<\/u><\/a> during the spacecraft&#8217;s 2014 rendezvous with Comet 67P, the D\/H value was roughly three times Earth&#8217;s. The researchers interpreted this as evidence that comets were very unlikely to have delivered water to Earth.<\/p>\n<p>The results were perplexing, Mandt said, because the D\/H value was way higher than those of other Jupiter-family comets. Plus, &#8220;the comet should have a lot more CO [carbon monoxide] and N2 [nitrogen] than Rosetta measured because these ices also form at really cold temperatures,&#8221; she added.<\/p>\n<p>To understand Comet 67P&#8217;s apparently high D\/H ratio, Mandt and other astronomers from research institutes in the U.S., France and Switzerland decided to comb through the entire Rosetta dataset. Using an innovative statistical technique developed by <a data-analytics-id=\"inline-link\" href=\"https:\/\/www.jhuapl.edu\/about\/people\/jacob-lustig-yaeger\" target=\"_blank\" data-url=\"https:\/\/www.jhuapl.edu\/about\/people\/jacob-lustig-yaeger\" referrerpolicy=\"no-referrer-when-downgrade\" data-hl-processed=\"none\" rel=\"noopener\"><u>Jacob Lustig-Yaeger<\/u><\/a> from the Johns Hopkins Applied Physics Laboratory, the team identified signals coming only from deuterium-containing water molecules, allowing them to collate about 4,000 D\/H measurements.<u><strong> <\/strong><\/u><\/p>\n<p>The researchers found that the D\/H values varied wildly along the comet&#8217;s long axis, with the highest being near the &#8220;nucleus&#8221; \u2014 the rocky part that resembles a rubber ducky \u2014 and decreasing along the tail.<\/p>\n<p>Such variation likely occurs because of processes occurring within the comet, the researchers wrote in their study, published Nov. 13 in the journal Science Advances. As the comet approaches <a data-analytics-id=\"inline-link\" href=\"https:\/\/www.livescience.com\/space\/astronomy\/the-sun\" data-before-rewrite-localise=\"https:\/\/www.livescience.com\/space\/astronomy\/the-sun\"><u>the sun<\/u><\/a>, the comet&#8217;s surface warms up, which releases gas along with ice-coated dust particles into the coma (the halo that develops around the nucleus). Previous, unrelated lab studies had shown that deuterium-containing ice tends to stick to dust grains more than to normal ice. The scientists realized that such dust grains, upon entering the coma, could account for the high D\/H values recorded there.<\/p>\n<p>However, the researchers noted that dust particles about 75 miles (120 kilometers) from the nucleus are essentially dried out, meaning they lack any deuterium-enriched ice that could generate spuriously high D\/H values. Using only the data collected at this distance, the authors calculated that Comet 67P&#8217;s actual D\/H value was only 1.5 times that of Earth.<\/p>\n<p>The revised D\/H value means that &#8220;all Jupiter Family Comets that we have been able to measure have a D\/H closer to the Earth&#8217;s water D\/H,&#8221; Mandt said. This implies that comets played a major, rather than minor, role in irrigating Earth. Plus, she added, a lower D\/H value suggests Comet 67P was born closer to the sun than scientists previously thought.<\/p>\n<\/div>\n<p><script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-3711241968723425\"\r\n     crossorigin=\"anonymous\"><\/script>\r\n<ins class=\"adsbygoogle\"\r\n     style=\"display:block\"\r\n     data-ad-format=\"fluid\"\r\n     data-ad-layout-key=\"-fb+5w+4e-db+86\"\r\n     data-ad-client=\"ca-pub-3711241968723425\"\r\n     data-ad-slot=\"7910942971\"><\/ins>\r\n<script>\r\n     (adsbygoogle = window.adsbygoogle || []).push({});\r\n<\/script><br \/>\n<br \/><div data-type=\"_mgwidget\" data-widget-id=\"1660802\">\r\n<\/div>\r\n<script>(function(w,q){w[q]=w[q]||[];w[q].push([\"_mgc.load\"])})(window,\"_mgq\");\r\n<\/script>\r\n<br \/>\n<br \/><a href=\"https:\/\/www.livescience.com\/space\/comets\/comets-played-a-major-role-in-making-life-on-earth-possible-new-study-hints\">Source link <\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>The idea that comets delivered water to early Earth has fallen out of favor in the past decade, but a new look at data from the European Space Agency&#8216;s (ESA) &hellip; <a href=\"https:\/\/hotvideos24.online\/?p=136343\" class=\"more-link\">Read More<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8628],"tags":[],"class_list":["post-136343","post","type-post","status-publish","format-standard","hentry","category-science","entry"],"_links":{"self":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/posts\/136343","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=136343"}],"version-history":[{"count":0,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=\/wp\/v2\/posts\/136343\/revisions"}],"wp:attachment":[{"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=136343"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=136343"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/hotvideos24.online\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=136343"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}