{"id":7893,"date":"2017-02-03T10:23:47","date_gmt":"2017-02-03T16:23:47","guid":{"rendered":"http:\/\/huewhite.com\/umb\/?p=7893"},"modified":"2017-02-03T10:23:47","modified_gmt":"2017-02-03T16:23:47","slug":"gravity-waves","status":"publish","type":"post","link":"https:\/\/huewhite.com\/umb\/2017\/02\/03\/gravity-waves\/","title":{"rendered":"Gravity Waves"},"content":{"rendered":"<p>A new one on me. <em><strong>NewScientist<\/strong><\/em> (21 January 2017) <a href=\"https:\/\/www.newscientist.com\/upfront\/3109\/\" target=\"_blank\">reports<\/a> on the possible detection of same on <em>Venus<\/em>:<\/p>\n<blockquote><p>A giant atmospheric phenomenon called a gravity wave has been spotted above Venus by the Japanese probe Akatsuki.<\/p><\/blockquote>\n<p>For those of us not keeping up, <em><strong>Wikipedia<\/strong><\/em> gives a <a href=\"https:\/\/en.wikipedia.org\/wiki\/Gravity_wave\" target=\"_blank\">definition<\/a>:<\/p>\n<blockquote><p>A gravity wave results when fluid is displaced from a position of <a title=\"Mechanical equilibrium\" href=\"https:\/\/en.wikipedia.org\/wiki\/Mechanical_equilibrium\">equilibrium<\/a>. The restoration of the fluid to equilibrium will produce a movement of the fluid back and forth, called a <i>wave orbit<\/i>.<sup id=\"cite_ref-1\" class=\"reference\"><a href=\"https:\/\/en.wikipedia.org\/wiki\/Gravity_wave#cite_note-1\">[1]<\/a><\/sup> Gravity waves on an air\u2013sea interface of the ocean are called <b>surface gravity waves<\/b> or <a title=\"Surface wave\" href=\"https:\/\/en.wikipedia.org\/wiki\/Surface_wave\">surface waves<\/a>, while gravity waves that are <i>within<\/i> the body of the water (such as between parts of different densities) are called <a title=\"Internal wave\" href=\"https:\/\/en.wikipedia.org\/wiki\/Internal_wave\">internal waves<\/a>. <a title=\"Wind wave\" href=\"https:\/\/en.wikipedia.org\/wiki\/Wind_wave\">Wind-generated waves<\/a> on the water surface are examples of gravity waves, as are <a title=\"Tsunami\" href=\"https:\/\/en.wikipedia.org\/wiki\/Tsunami\">tsunamis<\/a> and ocean <a title=\"Tide\" href=\"https:\/\/en.wikipedia.org\/wiki\/Tide\">tides<\/a>.<\/p><\/blockquote>\n<p>The <a href=\"http:\/\/www.nature.com\/ngeo\/journal\/v10\/n2\/full\/ngeo2873.html\" target=\"_blank\">abstract<\/a> of the technical paper from which the report is drawn:<\/p>\n<blockquote><p>The planet Venus is covered by thick clouds of sulfuric acid that move westwards because the entire upper atmosphere rotates much faster than the planet itself. At the cloud tops, about 65<span class=\"mb\">\u2009<\/span>km in altitude, small-scale features are predominantly carried by the background wind at speeds of approximately 100<span class=\"mb\">\u2009<\/span>m<span class=\"mb\">\u2009<\/span>s<sup>\u22121<\/sup>. In contrast, planetary-scale atmospheric features have been observed to move slightly faster or slower than the background wind, a phenomenon that has been interpreted to reflect the propagation of planetary-scale waves. Here we report the detection of an interhemispheric bow-shaped structure stretching 10,000<span class=\"mb\">\u2009<\/span>km across at the cloud-top level of Venus in middle infrared and ultraviolet images from the Japanese orbiter Akatsuki. Over several days of observation, the bow-shaped structure remained relatively fixed in position above the highland on the slowly rotating surface, despite the background atmospheric super\u00a0rotation. We suggest that the bow-shaped structure is the result of an atmospheric gravity wave generated in the lower atmosphere by mountain topography that then propagated upwards.<\/p><\/blockquote>\n<p><em><strong>Business Insider<\/strong><\/em> has a <a href=\"http:\/\/www.businessinsider.com\/venus-gravity-wave-akatsuki-2017-1\" target=\"_blank\">lovely pic<\/a> in infrared light:<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full\" src=\"http:\/\/static1.businessinsider.com\/image\/587d8e51ee14b68f7b8b5633-992\" width=\"992\" height=\"992\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>A new one on me. NewScientist (21 January 2017) reports on the possible detection of same on Venus: A giant atmospheric phenomenon called a gravity wave has been spotted above Venus by the Japanese probe Akatsuki. For those of us not keeping up, Wikipedia gives a definition: A gravity wave \u2026 <a class=\"continue-reading-link\" href=\"https:\/\/huewhite.com\/umb\/2017\/02\/03\/gravity-waves\/\"> Continue reading <span class=\"meta-nav\">&rarr; <\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-7893","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/huewhite.com\/umb\/wp-json\/wp\/v2\/posts\/7893","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/huewhite.com\/umb\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/huewhite.com\/umb\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/huewhite.com\/umb\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/huewhite.com\/umb\/wp-json\/wp\/v2\/comments?post=7893"}],"version-history":[{"count":1,"href":"https:\/\/huewhite.com\/umb\/wp-json\/wp\/v2\/posts\/7893\/revisions"}],"predecessor-version":[{"id":7894,"href":"https:\/\/huewhite.com\/umb\/wp-json\/wp\/v2\/posts\/7893\/revisions\/7894"}],"wp:attachment":[{"href":"https:\/\/huewhite.com\/umb\/wp-json\/wp\/v2\/media?parent=7893"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/huewhite.com\/umb\/wp-json\/wp\/v2\/categories?post=7893"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/huewhite.com\/umb\/wp-json\/wp\/v2\/tags?post=7893"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}