{"id":30504,"date":"2024-10-07T18:38:24","date_gmt":"2024-10-07T13:08:24","guid":{"rendered":"https:\/\/www.nextias.com\/ca\/?p=30504"},"modified":"2024-10-07T18:38:26","modified_gmt":"2024-10-07T13:08:26","slug":"planetary-defense-system","status":"publish","type":"post","link":"https:\/\/www.nextias.com\/ca\/current-affairs\/07-10-2024\/planetary-defense-system","title":{"rendered":"Planetary Defense System"},"content":{"rendered":"\n<p><strong>Syllabus: GS3\/ Science and technology<\/strong><\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Context<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Recently, the news regarding the potential threats of near-Earth objects (NEOs) was widespread due to asteroid <strong>2024 ON.<\/strong><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Impact of asteroids on Earth<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Around <strong>100 tons<\/strong> of space material hits Earth every day in the form of tiny meteoroids. These small fragments burn up in Earth&#8217;s atmosphere.<\/li>\n\n\n\n<li>Asteroids about <strong>50 meters <\/strong>in diameter are estimated to strike Earth once every 10,000 years.\n<ul class=\"wp-block-list\">\n<li><strong>In 2013<\/strong>, a 20-meter wide asteroid entered the atmosphere and exploded about 30 km above a Russian town.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>The most dangerous are those larger than<strong> 1 kilometer<\/strong> in diameter, like the <strong>Chicxulub asteroid<\/strong> that caused the extinction of the dinosaurs 66 million years ago.\u00a0<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-background\" style=\"background-color:#fff2cc\"><tbody><tr><td><strong>Asteroids<\/strong><br>&#8211; Asteroids, also known as <strong>minor planets or planetoids<\/strong>, are small, rocky bodies that orbit the Sun.\u00a0<br>&#8211; They are<strong> remnants of the solar system\u2019s formation,<\/strong> composed primarily of rock and metal.\u00a0<br>&#8211; <strong>Location: <\/strong>The majority of asteroids are found in the <strong>main asteroid belt<\/strong>, a region between the orbits of Mars and Jupiter.\u00a0<br>1. Some asteroids go in front of and behind Jupiter, which are called <strong>Trojans.\u00a0<\/strong><br>2. Asteroids that come close to Earth are called <strong>Near-Earth Objects (NEOs).<\/strong><br>&#8211; Based on their composition, asteroids are <strong>categorized into three types:<\/strong><br>1. <strong>C-type (carbonaceous): <\/strong>Rich in carbon, dark, and the most common type.<br>2. <strong>S-type (silicaceous):<\/strong> Made mostly of silicate materials and metals.<br>3. <strong>M-type (metallic): <\/strong>Composed mainly of metallic nickel-iron.<br><strong>Near-Earth Objects (NEOs)\u00a0<\/strong><br>&#8211; <strong>The United Nations Office for Outer Space Affairs (UNOOSA)<\/strong> defines NEOs as any asteroid or comet that comes close to Earth&#8217;s orbit.\u00a0<br>&#8211; In technical terms, an object is classified as a NEO if its perihelion (the point in its orbit closest to the Sun) is less than <strong>1.3 astronomical units (AU)<\/strong> from the Sun.\u00a0<br>1. <strong>One astronomical unit<\/strong> is the average distance between Earth and the Sun, about <strong>149.6 million kilometers.<\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Planetary Defense Efforts\u00a0<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Planetary defense<\/strong>, the detection of asteroids and comets whose impact with Earth could significantly affect the planet and the prevention or mitigation of any such impacts.<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>In 2022, NASA\u2019s Double Asteroid Redirection Test (DART) mission<\/strong> successfully crashed a spacecraft into an asteroid called Dimorphos. It demonstrated that a collision-based mission could change the direction of a celestial body and defend our planet.\n<ul class=\"wp-block-list\">\n<li><strong>ESA<\/strong> is scheduled to launch a reconnaissance mission called <strong>Hera<\/strong> in 2024 to inspect the aftermath left by DART.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>Several space missions have been sent to study asteroids up close and collect samples, such as\n<ul class=\"wp-block-list\">\n<li><strong>NASA\u2019s OSIRIS-REx mission<\/strong> to asteroid Bennu and\u00a0<\/li>\n\n\n\n<li><strong>Japan&#8217;s Hayabusa2 <\/strong>mission to asteroid Ryugu.\u00a0<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>India&#8217;s initiatives<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Also India is expected to collaborate with global planetary defense initiatives like <strong>International Asteroid Warning Network (IAWN)<\/strong>, a virtual network of institutions that work to detect, track, and characterize near-Earth objects (NEOs).\u00a0<\/li>\n\n\n\n<li>India and the US signed a <strong>Space situational awareness agreement <\/strong>in 2022.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Way Ahead<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Advances in space monitoring have improved the ability to predict and respond to potential threats.<\/li>\n\n\n\n<li>Scientists estimate that 95% of large, kilometer-sized NEOs have already been discovered, and none are expected to collide with Earth in the foreseeable future.<\/li>\n<\/ul>\n\n\n\n<p><strong>Source: <\/strong><a href=\"https:\/\/indianexpress.com\/article\/explained\/explained-sci-tech\/why-we-shouldnt-worry-too-much-about-an-asteroid-hitting-earth-9603894\/\" target=\"_blank\" rel=\"noopener\"><strong>IE<\/strong><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Recently, the news regarding the potential threats of near-Earth objects (NEOs) was widespread due to asteroid 2024 ON.<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[21],"tags":[],"class_list":["post-30504","post","type-post","status-publish","format-standard","hentry","category-current-affairs"],"acf":[],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/posts\/30504","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/comments?post=30504"}],"version-history":[{"count":1,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/posts\/30504\/revisions"}],"predecessor-version":[{"id":30505,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/posts\/30504\/revisions\/30505"}],"wp:attachment":[{"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/media?parent=30504"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/categories?post=30504"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.nextias.com\/ca\/wp-json\/wp\/v2\/tags?post=30504"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}