{"id":762,"date":"2002-05-31T10:45:00","date_gmt":"2002-05-31T10:45:00","guid":{"rendered":"https:\/\/ultrasparky.org\/blog\/2002\/05\/31\/metaphor_time_a\/"},"modified":"2024-11-30T03:15:04","modified_gmt":"2024-11-30T08:15:04","slug":"metaphor_time_a","status":"publish","type":"post","link":"https:\/\/ultrasparky.org\/blog\/2002\/05\/31\/metaphor_time_a\/","title":{"rendered":"Metaphor Time Again"},"content":{"rendered":"<p><strong>Astronomers don\u2019t expect to really see some of the things they look for.<\/strong> Instead, they have to reach conclusions from indirect observation to find things like <a title=\"The two planets orbiting Gliese 876 were detected the way most extrasolar planets are detected, using the Doppler effect.\" href=\"http:\/\/www.wired.com\/news\/technology\/0,1282,43865,00.html\">distant planets<\/a> or <a title=\"Astronomers several years ago saw a distant star brighten as a dark matter object passed in front it, a phenomenon known as gravitational lensing.\" href=\"http:\/\/www.wired.com\/news\/technology\/0,1282,48861,00.html\">dark matter<\/a>. They have to observe visible objects like stars and see how their views of these objects change as they are affected by the presence of the things they can&#8217;t see directly. Changes in light levels or color, properties that can be seen and recorded and measured, can be caused by the gravitational pull of these other, unseen objects as they pull the light source in one direction or another, or as their gravitational pull focuses the light like a lens, revealing sources of light that were otherwise too dim to notice.<\/p>\n<p>Which is to say, you don\u2019t always have to see something directly to know it\u2019s there. You can see how things change around that thing \u2014 how they directly respond to its presence \u2014 and the thing itself is revealed by these ripples in its environment. And then there it is, no secret at all.<\/p>\n<p><a title=\"Hubble's Top Ten Gravitational Lenses\" href=\"http:\/\/oposite.stsci.edu\/pubinfo\/PR\/1999\/18\/pr-photos.html\"><img decoding=\"async\" src=\"https:\/\/ultrasparky.org\/blog\/img\/hubble_lenses.jpg\" alt=\"Hubble's Top Ten Gravitational Lenses\" width=\"100%\" height=\"347\" border=\"0\" \/><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Astronomers don\u2019t expect to really see some of the things they look for. Instead, they have to reach conclusions from indirect observation to find things like distant planets or dark matter. They have to observe visible objects like stars and see how their views of these objects change as they are affected by the presence &hellip; <a href=\"https:\/\/ultrasparky.org\/blog\/2002\/05\/31\/metaphor_time_a\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Metaphor Time Again&#8221;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[],"class_list":["post-762","post","type-post","status-publish","format-standard","hentry","category-ultrapersonal"],"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/ultrasparky.org\/blog\/wp-json\/wp\/v2\/posts\/762","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ultrasparky.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ultrasparky.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ultrasparky.org\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/ultrasparky.org\/blog\/wp-json\/wp\/v2\/comments?post=762"}],"version-history":[{"count":2,"href":"https:\/\/ultrasparky.org\/blog\/wp-json\/wp\/v2\/posts\/762\/revisions"}],"predecessor-version":[{"id":77075,"href":"https:\/\/ultrasparky.org\/blog\/wp-json\/wp\/v2\/posts\/762\/revisions\/77075"}],"wp:attachment":[{"href":"https:\/\/ultrasparky.org\/blog\/wp-json\/wp\/v2\/media?parent=762"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ultrasparky.org\/blog\/wp-json\/wp\/v2\/categories?post=762"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ultrasparky.org\/blog\/wp-json\/wp\/v2\/tags?post=762"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}