{"id":2859,"date":"2025-06-17T12:55:07","date_gmt":"2025-06-17T07:25:07","guid":{"rendered":"https:\/\/vajiramandravi.com\/current-affairs\/?p=2859"},"modified":"2025-06-17T14:16:01","modified_gmt":"2025-06-17T08:46:01","slug":"synthetic-aperture-radar","status":"publish","type":"post","link":"https:\/\/vajiramandravi.com\/current-affairs\/synthetic-aperture-radar\/","title":{"rendered":"What is Synthetic Aperture Radar?"},"content":{"rendered":"<h2><strong>Synthetic Aperture Radar Latest News<\/strong><\/h2>\n<p><span style=\"font-weight: 400;\">Recently, NASA said the NASA-ISRO SAR mission had arrived at ISRO\u2019s spaceport in Sriharikota.<\/span><\/p>\n<h2><b>About Synthetic Aperture Radar<\/b><\/h2>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">It is a type of <\/span><b>active data collection<\/b><span style=\"font-weight: 400;\"> where an instrument sends out a pulse of energy and then records the amount of that energy reflected back after it interacts with Earth.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">SAR imagery is <\/span><b>created from the reaction of an emitted pulse<\/b><span style=\"font-weight: 400;\"> of energy with physical structures (like mountains, forests, and sea ice) and conditions like soil moisture.\u00a0<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">It is a way to make sharp pictures even when it\u2019s dark or cloudy.<\/span><\/li>\n<\/ul>\n<h2><b>Working of Synthetic Aperture Radar<\/b><\/h2>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">SAR systems <\/span><b>send out microwave pulses<\/b><span style=\"font-weight: 400;\"> and record the echoes that bounce back from the ground, ocean, ice or buildings.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Then, clever signal processing turns those echoes into detailed images.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The key element is the antenna that receives the echoes. Usually, the longer a physical antenna, the better the resolution \u2014 but a large antenna is hard to build and maintain.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">On a SAR, a small antenna is <\/span><b>carried on a moving platform like a satellite<\/b><span style=\"font-weight: 400;\">. As a result each echo is recorded at a slightly different position.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">By stitching them together with precise timing and phase information, software can help mimic a single antenna hundreds of metres long.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Since microwaves penetrate clouds, smoke, and even light rainfall, <\/span><b>SAR can collect data 24\/7.<\/b><span style=\"font-weight: 400;\"> If a SAR unit is mounted on an orbiting satellite, it can map swaths of land hundreds of kilometres wide in a single overpass.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Different materials like soil, vegetation, water, and metals reflect microwaves differently, allowing SAR to <\/span><b>detect changes invisible to optical sensors.<\/b><\/li>\n<\/ul>\n<p><b>Source: <\/b><a href=\"https:\/\/www.thehindu.com\/sci-tech\/science\/what-is-synthetic-aperture-radar\/article69703378.ece\" target=\"_blank\" rel=\"nofollow noopener\"><b>TH<\/b><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Synthetic Aperture Radar is a type of active data collection where an instrument sends out a pulse of energy and then records the amount of that energy reflected back after it interacts with Earth.<\/p>\n","protected":false},"author":5,"featured_media":50667,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[21,885,22,23],"class_list":{"0":"post-2859","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-upsc-prelims-current-affairs","8":"tag-prelims-pointers","9":"tag-synthetic-aperture-radar","10":"tag-upsc-current-affairs","11":"tag-upsc-prelims-current-affairs","12":"no-featured-image-padding"},"acf":[],"_links":{"self":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/2859","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\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/comments?post=2859"}],"version-history":[{"count":0,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/posts\/2859\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media\/50667"}],"wp:attachment":[{"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/media?parent=2859"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/categories?post=2859"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vajiramandravi.com\/current-affairs\/wp-json\/wp\/v2\/tags?post=2859"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}