{"id":2149,"date":"2009-01-06T15:54:25","date_gmt":"2009-01-06T20:54:25","guid":{"rendered":"http:\/\/www.allyngibson.net\/?p=2149"},"modified":"2009-01-06T15:54:25","modified_gmt":"2009-01-06T20:54:25","slug":"on-the-universe-we-live-in","status":"publish","type":"post","link":"http:\/\/www.allyngibson.com\/?p=2149","title":{"rendered":"On the Universe We Live In"},"content":{"rendered":"<p>Sometimes, I <i>really<\/i> wish I could live to see the world three billion years hence.<\/p>\n<p>Okay, I take that back.  It&#8217;s not just sometimes.  I wish that <i>all<\/i> the time.<\/p>\n<p>In three billion years, give or take a few hundred million years, astronomers believe that <a href=\"http:\/\/www.haydenplanetarium.org\/resources\/ava\/galaxies\/G0601andmilwy\">the Milky Way, our home galaxy, and M-31, better known as the Andromeda Galaxy, will collide<\/a>.<\/p>\n<p>Oh, to be alive then! To see a barred spiral galaxy dominate the night sky for millions of years, and then to stand somewhere outside the galaxy and watch as the arms of the two galaxies comingle.<\/p>\n<p>Why can&#8217;t it happen <i>now<\/i>?  Why must things happen on a cosmic scale where we humans are merely dust motes that matter not at all, where the span of our existence registers as nothing in the grand scale of time?<\/p>\n<p>Alas, I can bemoan the cosmic unfairness of it, content myself with watching simulations of what <i>might<\/i> happen, read <a href=\"http:\/\/en.wikipedia.org\/wiki\/Andromeda-Milky_Way_collision\">Wikipedia articles<\/a> until I&#8217;m bored out of my skull.<\/p>\n<p>Such is my life.<\/p>\n<p>Then I read this today &mdash; <a href='http:\/\/news.bbc.co.uk\/2\/hi\/science\/nature\/7813635.stm'>our own galaxy is larger than scientists had previously thought<\/a>.<\/p>\n<p>For a number of years, the Andromeda Galaxy was believed to dwarf the Milky Way.  But as radio astronomy has improved as we&#8217;ve had better tools to chart the heavens, many of the assumptions about a galaxy have been altered.  For many years our galaxy was believed to be a true spiral, but now we know that it is a barred spiral.  Now we know that the galaxy rotates faster than had been previously believed; a faster rotation means a greater mass.<\/p>\n<blockquote><p>The researchers estimate that the Milky Way contains about 50% more mass than earlier predictions &#8211; putting it on a par with the Andromeda galaxy, previously thought to be our much bigger neighbour and the largest in our Local Group of galaxies. <\/p>\n<p>&#8220;No longer will we think of the Milky Way as the little sister of the Andromeda Galaxy,&#8221; Dr Reid said. <\/p>\n<p>That higher mass makes for a higher gravitational pull, suggesting that collisions with Andromeda and other nearby galaxies may happen much sooner than thought &#8211; but still billions of years in the future.<\/p><\/blockquote>\n<p>So that far distant collision between the Milky Way and Andromeda?  It might only be 2 and a half billion years away, not that <i>impossibly<\/i> far distant 3 billion years.  I won&#8217;t have to live <i>quite<\/i> as long. \ud83d\ude09<\/p>\n<p>The Earth will still exist then.  Our solar system will still be here.  Sol has another five billion years of life left to it.  I wonder what strange creatures will inhabit the Earth billions of years from now.  Will they be descended from us?  Or will evolution have taken a different path, so it is descendents of blowfish, for example, that have inherited the Earth?<\/p>\n<p>Too bad I won&#8217;t see it.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Sometimes, I really wish I could live to see the world three billion years hence. Okay, I take that back. It&#8217;s not just sometimes. I wish that all the time. In three billion years, give or take a few hundred million years, astronomers believe that the Milky Way, our home galaxy, and M-31, better known<a class=\"more-link\" href=\"http:\/\/www.allyngibson.com\/?p=2149\">Continue reading <span class=\"screen-reader-text\">&#8220;On the Universe We Live In&#8221;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[128],"tags":[654,4111,655],"class_list":["post-2149","post","type-post","status-publish","format-standard","hentry","category-astronomy","tag-andromeda","tag-astronomy","tag-milky-way","entry"],"_links":{"self":[{"href":"http:\/\/www.allyngibson.com\/index.php?rest_route=\/wp\/v2\/posts\/2149","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.allyngibson.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.allyngibson.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.allyngibson.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/www.allyngibson.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2149"}],"version-history":[{"count":0,"href":"http:\/\/www.allyngibson.com\/index.php?rest_route=\/wp\/v2\/posts\/2149\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.allyngibson.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2149"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.allyngibson.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2149"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.allyngibson.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2149"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}