{"id":13377,"date":"2014-02-07T21:45:37","date_gmt":"2014-02-07T21:45:37","guid":{"rendered":"http:\/\/www.mometrix.com\/academy\/?page_id=13377"},"modified":"2026-03-26T09:31:53","modified_gmt":"2026-03-26T14:31:53","slug":"tilt-of-earth-and-seasons","status":"publish","type":"page","link":"https:\/\/www.mometrix.com\/academy\/tilt-of-earth-and-seasons\/","title":{"rendered":"Earth\u2019s Tilt and Seasons"},"content":{"rendered":"\n\t\t\t<div id=\"mmDeferVideoEncompass_IYKoUhZbqsk\" style=\"position: relative;\">\n\t\t\t<picture>\n\t\t\t\t<source srcset=\"https:\/\/www.mometrix.com\/academy\/wp-content\/uploads\/2023\/01\/circle-play-duotone.webp\" type=\"image\/webp\">\n\t\t\t\t<source srcset=\"https:\/\/www.mometrix.com\/academy\/wp-content\/uploads\/2023\/01\/circle-play-duotone.png\" type=\"image\/jpeg\"> \n\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" loading=\"eager\" id=\"videoThumbnailImage_IYKoUhZbqsk\" data-source-videoID=\"IYKoUhZbqsk\" src=\"https:\/\/www.mometrix.com\/academy\/wp-content\/uploads\/2023\/01\/circle-play-duotone.png\" alt=\"Earth\u2019s Tilt and Seasons Video\" height=\"1080\" width=\"1920\" class=\"size-full\" data-matomo-title = \"Earth\u2019s Tilt and Seasons\">\n\t\t\t<\/picture>\n\t\t\t<\/div>\n\t\t\t<style>img#videoThumbnailImage_IYKoUhZbqsk:hover {cursor:pointer;} img#videoThumbnailImage_IYKoUhZbqsk {background-size:contain;background-image:url(\"https:\/\/www.mometrix.com\/academy\/wp-content\/uploads\/2023\/07\/updated-earths-tilt-and-seasons-64c1657ad4163.webp\");}<\/style>\n\t\t\t<script defer>\n\t\t\t  jQuery(\"img#videoThumbnailImage_IYKoUhZbqsk\").click(function() {\n\t\t\t\tlet videoId = jQuery(this).attr(\"data-source-videoID\");\n\t\t\t\tlet helpTag = '<div id=\"mmDeferVideoYTMessage_IYKoUhZbqsk\" style=\"display: none;position: absolute;top: -24px;width: 100%;text-align: center;\"><span style=\"font-style: italic;font-size: small;border-top: 1px solid #fc0;\">Having trouble? <a href=\"https:\/\/www.youtube.com\/watch?v='+videoId+'\" target=\"_blank\">Click here to watch on YouTube.<\/a><\/span><\/div>';\n\t\t\t\tlet tag = document.createElement(\"iframe\");\n\t\t\t\ttag.id = \"yt\" + videoId;\n\t\t\t\ttag.src = \"https:\/\/www.youtube-nocookie.com\/embed\/\" + videoId + \"?autoplay=1&controls=1&wmode=opaque&rel=0&egm=0&iv_load_policy=3&hd=0&enablejsapi=1\";\n\t\t\t\ttag.frameborder = 0;\n\t\t\t\ttag.allow = \"autoplay; fullscreen\";\n\t\t\t\ttag.width = this.width;\n\t\t\t\ttag.height = this.height;\n\t\t\t\ttag.setAttribute(\"data-matomo-title\",\"Earth\u2019s Tilt and Seasons\");\n\t\t\t\tjQuery(\"div#mmDeferVideoEncompass_IYKoUhZbqsk\").html(tag);\n\t\t\t\tjQuery(\"div#mmDeferVideoEncompass_IYKoUhZbqsk\").prepend(helpTag);\n\t\t\t\tsetTimeout(function(){jQuery(\"div#mmDeferVideoYTMessage_IYKoUhZbqsk\").css(\"display\", \"block\");}, 2000);\n\t\t\t  });\n\t\t\t  \n\t\t\t<\/script>\n\t\t\n<p><script>\nfunction MyR_Function() {\n  var x = document.getElementById(\"MyR\");\n  if (x.style.display === \"none\") {\n    x.style.display = \"block\";\n  } else {\n    x.style.display = \"none\";\n  }\n}\n<\/script><\/p>\n<div class=\"moc-toc hide-on-desktop hide-on-tablet\">\n<div><button onclick=\"MyR_Function()\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.mometrix.com\/academy\/wp-content\/uploads\/2024\/12\/toc2.svg\" width=\"16\" height=\"16\" alt=\"show or hide table of contents\"><\/button><\/p>\n<p>On this page<\/p>\n<\/div>\n<nav id=\"MyR\" style=\"display:none;\">\n<ul>\n<li class=\"toc-h2\"><a href=\"#Earth%E2%80%99s_Orbital_Dynamics\" class=\"smooth-scroll\">Earth\u2019s Orbital Dynamics<\/a><\/li>\n<li class=\"toc-h2\"><a href=\"#Seasonal_Changes\" class=\"smooth-scroll\">Seasonal Changes<\/a><\/li>\n<li class=\"toc-h2\"><a href=\"#Review_Questions\" class=\"smooth-scroll\">Review Questions<\/a><\/li>\n<\/ul>\n<\/nav>\n<\/div>\n<div class=\"accordion\"><input id=\"transcript\" type=\"checkbox\" class=\"spoiler_button\" \/><label for=\"transcript\">Transcript<\/label>\n<div class=\"spoiler\" id=\"transcript-spoiler\">\n<p>Hi, and welcome to this video on the tilt of the Earth! Today, we will be learning how the Earth&#8217;s tilt affects the four seasons, the temperature, and the summer and winter solstices.<\/p>\n<h2>Earth&#8217;s Orbital Dynamics<\/h2>\n<p>\nSo, hopefully you know that Earth (and the rest of the planets) rotate around the Sun. One trip around the Sun is equal to one year. The official name for this \u201ctrip\u201d is called an orbit, and one complete Earth orbit, as we know, takes 365 days. Jupiter\u2019s orbit, for comparison, takes 12 Earth years. Jupiter is a lot further from the Sun than we are, so as you can imagine, it has a longer distance to travel.<\/p>\n<p>The Earth rotates around the Sun, but it also rotates around an <strong>internal axis<\/strong>. A great way to visualize this concept is to think about a top.<\/p>\n<p>Notice how each of these tops has a long end and a pointy end. Draw an imaginary line through both of these ends, and you have an axis. The top will always rotate or spin around this same imaginary line.<\/p>\n<p>The same is true for the Earth. Earth always spins or rotates around the same imaginary line. <\/p>\n<p>However, Earth\u2019s axis isn\u2019t straight up and down like a top; it\u2019s angled at 23.5\u00b0. At least\u2026it is right now. Over the course of about 40,000 years, this angle will cycle between 22.1\u00b0 and 24.5\u00b0.<\/p>\n<p>You might have heard before that Earth\u2019s tilt is what allows our planet to have different seasons. If you\u2019re in the Northern Hemisphere, you\u2019ll have winter when it\u2019s cold, summer when it\u2019s hot, and spring and fall in between. With our current tilt of 23.5\u00b0, these seasons are pretty mild. With a lower axial tilt of 22.1\u00b0, they would be even more uniform\u2014a larger tilt of 24.5\u00b0 would mean more extreme seasons. Let\u2019s take a look at why this is.<\/p>\n<p>Even though Earth\u2019s axis is tilted, the Sun\u2019s rays are still hitting our planet horizontally. Depending on what time of year it is (i.e. what season it is), the tilt of the earth will directly affect the amount of sunlight that different tropics will receive. And when I say tropics, I\u2019m referring to either the Tropic of Cancer or the Tropic of Capricorn. The <strong>Tropic of Cancer<\/strong> is an imaginary line that circles the globe parallel to the Equator, at 23.5\u00b0 N latitude \u2013 and the <strong>Tropic of Capricorn<\/strong> is an imaginary line at 23.5\u00b0 S latitude. <\/p>\n<p>Okay, now that we know WHERE these tropics are, we know that the Earth rotates around a tilted axis, and we know that it orbits around the Sun, let\u2019s put all these together. We will go season by season, so let\u2019s start with spring first.<\/p>\n<h2><span id=\"Seasonal_Changes\" class=\"m-toc-anchor\"><\/span>Seasonal Changes<\/h2>\n<p>\nTake a look at the horizontal rays coming in on the left side from the Sun. The rays are coming in horizontally, but because our planet is a globe, there is only one spot where these rays are hitting at a perpendicular angle. Looking at this image, can you tell where it is? If you said the Equator, you\u2019re right! When the Sun\u2019s rays hit a line of latitude at a perpendicular angle, that is where the most direct sunlight is received. When rays hit at less than a 90\u00b0 angle, the sunlight is spread over a much larger area, so heat is dispersed instead of concentrated.<\/p>\n<p>We\u2019ve learned a lot from this image so far: In the spring time, the Sun\u2019s rays hit the Equator at a perpendicular angle, meaning it receives the most direct, concentrated sunlight. The Tropic of Cancer and Tropic of Capricorn receive equal amounts of sunlight as each other, as do the <strong>Arctic Circle<\/strong> and <strong>Antarctic Circle<\/strong>.<\/p>\n<p>One other thing I want to point out from this image is the amount of daylight that we experience in the spring time. Because Earth is tilted on its axis at this point (not tilted toward or away from the Sun), all areas of the globe will receive equal amounts of daylight and darkness: 12 hours of each. The first day of spring, as shown here, is called the vernal equinox, meaning equal daylight and darkness. As spring turns into summer, the days grow longer and the nights become shorter.<\/p>\n<p>When we talk about summer, we\u2019re going to refer to this as the \u201cNorthern Hemisphere\u201d summer, since that is what the United States experiences.<\/p>\n<p>This is showing the first day of summer, which is called the <strong>summer solstice<\/strong>. The solstices represent the Earth at its closest or farthest from the Sun in its orbit. During the Northern Hemisphere&#8217;s summer solstice, the Southern Hemisphere is experiencing its winter solstice. Take a look at Earth\u2019s axis, now. We can see how it\u2019s sort of tilted toward the Sun. Can you determine at which latitude the Sun\u2019s rays are hitting our planet at a 90\u00b0 angle? This time, it\u2019s the Tropic of Cancer. At the Tropic of Cancer during Northern Hemisphere summer, Earth receives the most direct, concentrated sunlight. During North America&#8217;s summer season, the increase in direct sunlight causes a rise in temperatures. More sunlight equals more heat!<\/p>\n<p>Now, take a look at the Antarctic Circle. Imagine the Earth spinning in this location around its axis. Are you able to visualize how this particular area of the globe is always in the shaded region? This means that many regions in the Antarctic Circle experience a \u201cpolar night,\u201d which is when darkness lasts for more than 24 hours. During Northern Hemisphere summer, the Antarctic Circle receives the least amount of sunlight.<\/p>\n<p>Conversely, check out the Arctic Circle and visualize how, when the Earth rotates around its axis, it is always in the lit-up region. The Arctic Circle experiences a \u201cPolar Day\u201d during summer, when the Sun is above the horizon for more than 24 hours. In summer time, the Arctic Circle receives the most amount of sunlight.<\/p>\n<p>Now, let\u2019s talk about fall!<\/p>\n<p>Looks the same as the <strong>Vernal Equinox<\/strong>, right? That\u2019s because this is the <strong>Autumnal Equinox<\/strong>! Again, the Earth is neither tilted toward or away from the Sun, but more \u201con its side,\u201d so all areas of the globe receive equal amounts of daylight and darkness. Once again, the Equator receives the most direct, concentrated sunlight.<\/p>\n<p>Next up is winter time; in particular the <strong>Winter Solstice<\/strong>. This is the same deal as the summer time, except now the Earth is tilted away from the Sun. Where are the Sun\u2019s rays hitting at a perpendicular angle? This time, it\u2019s the Tropic of Capricorn, located at 23.5\u00b0 South. While the most concentrated, direct sunlight is hitting the Southern Hemisphere, the Northern Hemisphere is experiencing the colder temperatures of its winter season as the Southern Hemisphere enjoys the warmth of summer.<\/p>\n<p>During North American winter, the Antarctic Circle gets their Polar Day, while the Arctic Circle experiences a Polar Night.<\/p>\n<p>One more thing to note about all these scenarios is that along the Equator, it will always receive the same amount of daylight and darkness no matter what season it is. This is because of the Equator&#8217;s central location and equal distances from the North and South Pole.<\/p>\n<p>Once the Earth has made it all the way around the Sun, the cycle restarts!<\/p>\n<p>Ok, before we go, let\u2019s go over a couple of quick review questions!<\/p>\n<hr>\n<h2><span id=\"Review_Questions\" class=\"m-toc-anchor\"><\/span>Review Questions<\/h2>\n<p>1. What is the current tilt of Earth\u2019s axis?<\/p>\n<ol style=\"list-style: upper-alpha;\">\n<li>22.1\u00b0<\/li>\n<li>90\u00b0<\/li>\n<li>23.5\u00b0<\/li>\n<li>24.5\u00b0<\/li>\n<\/ol>\n<div style=\"text-align: center; margin-bottom: 20px;\">\n   <button class=\"buttontranscript\" onClick=\"toggle('Answer1')\">Show Answer<\/button>\n<\/div>\n<div id=\"Answer1\" class=\"showanswer\">\n   <strong>The correct answer is C.<\/strong><\/p>\n<p style=\"text-align: left;\">The axial tilt will cycle between 22.1\u00b0 and 24.5\u00b0 over a 40,000-year period.<\/p>\n<\/div>\n<p>\n&nbsp;<br \/>\n2. When will areas of the Antarctic Circle experience a Polar Night?<\/p>\n<ol style=\"list-style: upper-alpha;\">\n<li>Summer Solstice<\/li>\n<li>Vernal Equinox<\/li>\n<li>Winter Solstice<\/li>\n<li>Autumnal Equinox<\/li>\n<\/ol>\n<div style=\"text-align: center; margin-bottom: 20px;\">\n   <button class=\"buttontranscript\" onClick=\"toggle('Answer2')\">Show Answer<\/button>\n<\/div>\n<div id=\"Answer2\" class=\"showanswer\">\n   <strong>The correct answer is A.<\/strong><\/p>\n<p style=\"text-align: left;\">Summer Solstice! During the Northern Hemisphere\u2019s Summer, the Earth is tilted toward the Sun, so the poor South Pole will receive the least amount of sunlight \u2013 some parts in darkness for over 24 hours.\n<\/p>\n<\/div>\n<p>\n&nbsp;<br \/>\nThat\u2019s all for this review! Thanks for watching, and happy studying!<\/p>\n<\/div>\n<\/div>\n\n<div class=\"home-buttons\">\n<p><a href=\"https:\/\/www.mometrix.com\/academy\/environmental\/\">Return to Environmental Videos<\/a><\/p>\n<\/div>\n<p><script>\nfunction toggle(obj) {\n          var obj=document.getElementById(obj);\n          if (obj.style.display == \"block\") obj.style.display = \"none\";\n          else obj.style.display = \"block\";\n}\n<\/script><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Return to Environmental Videos<\/p>\n","protected":false},"author":1,"featured_media":187304,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"open","template":"","meta":{"footnotes":""},"class_list":{"0":"post-13377","1":"page","2":"type-page","3":"status-publish","4":"has-post-thumbnail","6":"page_category-environmental-videos","7":"page_category-video-pages-for-study-course-sidebar-ad","8":"page_type-video","9":"subject_matter-science"},"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.mometrix.com\/academy\/wp-json\/wp\/v2\/pages\/13377","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.mometrix.com\/academy\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.mometrix.com\/academy\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.mometrix.com\/academy\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.mometrix.com\/academy\/wp-json\/wp\/v2\/comments?post=13377"}],"version-history":[{"count":6,"href":"https:\/\/www.mometrix.com\/academy\/wp-json\/wp\/v2\/pages\/13377\/revisions"}],"predecessor-version":[{"id":281834,"href":"https:\/\/www.mometrix.com\/academy\/wp-json\/wp\/v2\/pages\/13377\/revisions\/281834"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.mometrix.com\/academy\/wp-json\/wp\/v2\/media\/187304"}],"wp:attachment":[{"href":"https:\/\/www.mometrix.com\/academy\/wp-json\/wp\/v2\/media?parent=13377"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}