{"id":48286,"date":"2025-04-30T17:18:44","date_gmt":"2025-04-30T11:48:44","guid":{"rendered":"https:\/\/vajiramandravi.com\/current-affairs\/?p=48286"},"modified":"2025-05-28T17:20:48","modified_gmt":"2025-05-28T11:50:48","slug":"near-surface-shear-layer","status":"publish","type":"post","link":"https:\/\/vajiramandravi.com\/current-affairs\/near-surface-shear-layer\/","title":{"rendered":"Near-Surface Shear Layer (NSSL)"},"content":{"rendered":"<h2>Near-Surface Shear Layer (NSSL) Latest News<\/h2>\n<p>An international team of solar physicists, including scientists from the Indian Institute of Astrophysics (IIA), has mapped dynamic plasma currents in the Sun\u2019s Near-Surface Shear Layer (NSSL), revealing patterns that correlate with the Sun\u2019s 11-year magnetic activity (sunspot) cycle.<\/p>\n<h2>About Near-Surface Shear Layer (NSSL) &amp; Key Findings<\/h2>\n<ul>\n<li><strong>The Near-Surface Shear Layer (NSSL)<\/strong>\u00a0is a crucial region located just beneath the\u00a0<strong>Sun\u2019s visible surface<\/strong>, extending to a depth of about\u00a0<strong>35,000 km<\/strong>.<\/li>\n<li>In the\u00a0<strong>NSSL<\/strong>, the\u00a0<strong>Sun&#8217;s angular velocity (rotation speed)<\/strong>\u00a0decreases rapidly with radius, creating a\u00a0<strong>rotational shear<\/strong>\u00a0that varies with\u00a0<strong>depth, latitude, and solar magnetic activity<\/strong>.<\/li>\n<li>The study revealed\u00a0<strong>surface plasma flows converge towards sunspot latitudes<\/strong>\u00a0but reverse midway in the NSSL and\u00a0<strong>flow outward<\/strong>, forming large\u00a0<strong>circulation cells<\/strong>.<\/li>\n<li>These\u00a0<strong>flows are shaped by the Sun&#8217;s rotation and the Coriolis force<\/strong>, which also influences Earth&#8217;s hurricanes. This connection helps explain how the Sun&#8217;s spin behaviour varies with depth.<\/li>\n<li>Despite being dynamic, these\u00a0<strong>localised flows do not drive the Sun&#8217;s large-scale zonal flows<\/strong>, known as\u00a0<strong>torsional oscillations<\/strong>, implying the\u00a0<strong>presence of deeper unknown forces<\/strong>\u00a0in the Sun\u2019s interior.<\/li>\n<\/ul>\n<h3>Techniques Used<\/h3>\n<ul>\n<li>Scientists employed\u00a0<strong>helioseismology<\/strong>, a method that uses\u00a0<strong>sound waves<\/strong>\u00a0travelling inside the Sun to\u00a0<strong>map internal structures<\/strong>\u00a0and dynamics.<\/li>\n<li>They used over a decade\u2019s worth of data from:\n<ul>\n<li><strong>NASA\u2019s Solar Dynamics Observatory (SDO)<\/strong>, specifically the\u00a0<strong>Helioseismic and Magnetic Imager (HMI)<\/strong>, and<\/li>\n<li>The\u00a0<strong>Global Oscillations Network Group (GONG)<\/strong>\u00a0of the\u00a0<strong>National Solar Observatory (NSO), USA<\/strong>.<\/li>\n<\/ul>\n<\/li>\n<li>The research confirmed the findings using\u00a0<strong>3D velocity maps of sunspot regions<\/strong>, showing matching\u00a0<strong>surface inflows<\/strong>\u00a0and\u00a0<strong>deeper outflows<\/strong>.<\/li>\n<\/ul>\n<h2>Near-Surface Shear Layer (NSSL) FAQs<\/h2>\n<p><strong>Q1.\u00a0<\/strong>What is the Near-Surface Shear Layer (NSSL)?<br \/>\n<strong>Ans.<\/strong>\u00a0NSSL is a thin zone beneath the Sun\u2019s surface where the rotation rate of solar plasma changes rapidly with depth, affecting solar dynamics and sunspots.<\/p>\n<p><strong>Q2.\u00a0<\/strong>Why is NSSL important in solar physics?<br \/>\n<strong>Ans.<\/strong>\u00a0NSSL helps scientists understand solar magnetic fields, solar cycles, and space weather phenomena like solar flares.<\/p>\n<p><strong>Q3.<\/strong>\u00a0Which mission has studied the NSSL recently?<br \/>\n<strong>Ans.<\/strong>\u00a0The Solar Orbiter (ESA) and NASA\u2019s Solar Dynamics Observatory have provided key data to study the NSSL.<\/p>\n<p><strong>Source:\u00a0<\/strong><a href=\"https:\/\/pib.gov.in\/PressReleasePage.aspx?PRID=2125195\" target=\"_blank\" rel=\"nofollow noopener\">PIB<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>NSSL is a thin zone beneath the Sun\u2019s surface where the rotation rate of solar plasma changes rapidly with depth, affecting solar dynamics and sunspots.<\/p>\n","protected":false},"author":8,"featured_media":48289,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[586,21,23],"class_list":{"0":"post-48286","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-upsc-prelims-current-affairs","8":"tag-near-surface-shear-layer-nssl","9":"tag-prelims-pointers","10":"tag-upsc-prelims-current-affairs","11":"no-featured-image-padding"},"acf":[],"_links":{"self":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/48286","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/comments?post=48286"}],"version-history":[{"count":0,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/48286\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media\/48289"}],"wp:attachment":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media?parent=48286"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/categories?post=48286"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/tags?post=48286"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}