{"version":"1.0","provider_name":"Glossary","provider_url":"https:\/\/www.healthbenefitstimes.com\/glossary","author_name":"Glossary","author_url":"https:\/\/www.healthbenefitstimes.com\/glossary\/author\/adminglossary\/","title":"Nebular hypothesis - Definition of Nebular hypothesis","type":"rich","width":600,"height":338,"html":"<blockquote class=\"wp-embedded-content\" data-secret=\"sDuHW7qAyc\"><a href=\"https:\/\/www.healthbenefitstimes.com\/glossary\/nebular-hypothesis\/\">Nebular hypothesis<\/a><\/blockquote><iframe sandbox=\"allow-scripts\" security=\"restricted\" src=\"https:\/\/www.healthbenefitstimes.com\/glossary\/nebular-hypothesis\/embed\/#?secret=sDuHW7qAyc\" width=\"600\" height=\"338\" title=\"&#8220;Nebular hypothesis&#8221; &#8212; Glossary\" data-secret=\"sDuHW7qAyc\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\" class=\"wp-embedded-content\"><\/iframe><script>\n\/*! This file is auto-generated *\/\n!function(d,l){\"use strict\";l.querySelector&&d.addEventListener&&\"undefined\"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!\/[^a-zA-Z0-9]\/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret=\"'+t.secret+'\"]'),o=l.querySelectorAll('blockquote[data-secret=\"'+t.secret+'\"]'),c=new RegExp(\"^https?:$\",\"i\"),i=0;i<o.length;i++)o[i].style.display=\"none\";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute(\"style\"),\"height\"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):\"link\"===t.message&&(r=new URL(s.getAttribute(\"src\")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener(\"message\",d.wp.receiveEmbedMessage,!1),l.addEventListener(\"DOMContentLoaded\",function(){for(var e,t,s=l.querySelectorAll(\"iframe.wp-embedded-content\"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute(\"data-secret\"))||(t=Math.random().toString(36).substring(2,12),e.src+=\"#?secret=\"+t,e.setAttribute(\"data-secret\",t)),e.contentWindow.postMessage({message:\"ready\",secret:t},\"*\")},!1)))}(window,document);\n\/\/# sourceURL=https:\/\/www.healthbenefitstimes.com\/glossary\/wp-includes\/js\/wp-embed.min.js\n<\/script>\n","description":"A theory of the formation of the Sun\u2019s planetary system advanced by Pierre Simon Laplace (1749-1827) in his Exposition du Systeme du Monde (1796). He theorized that gravity would condense a rotating disc of matter with most of its mass near the center into a massive central body and a number of much smaller orbiting planets. The theory gave a plausible explanation of why all the planets orbit in the same direction and why their orbits are in approximately the same plane.In 1873, James Clerk Maxwell (1831-79) showed theoretically that radiation would exert a pressure on any surface on which it fell. This was confirmed experimentally in 1900. Sunlight, for example, is calculated to exert a pressure of about 2 pounds per square mile, so small as to be difficult to measure. But in the interior of stars and galaxies where the radiation intensity is much higher, radiation pressure is a significant factor. In 1900 two scientists in the University of Chicago showed that the Maxwell radiation pressure in a disc of the size required in the nebular hypothesis would counterbalance the gravitational forces and prevent condensation; they advanced an alternative theory. Sir James Jeans later showed that the radiation-pressure difficulty only held for astronomically small aggregations such as the solar system and that the nebular hypothesis could explain the condensation of stars from a galactic disc."}