{"id":3147,"date":"2020-05-22T12:19:44","date_gmt":"2020-05-22T11:19:44","guid":{"rendered":"http:\/\/abergavennyas.org.uk\/?p=3147"},"modified":"2020-05-22T12:19:44","modified_gmt":"2020-05-22T11:19:44","slug":"planet-9-what-are-you-physicsworld-19th-may","status":"publish","type":"post","link":"http:\/\/abergavennyas.org.uk\/?p=3147","title":{"rendered":"Planet 9 &#8211; What are you? (PhysicsWorld 19th May)"},"content":{"rendered":"<p>Pluto may have been demoted from planet status back in 2006 but astronomers are still trying to explain the orbits of a number of other Kuiper Belt objects which are in highly elliptical orbits.<\/p>\n<p><a href=\"http:\/\/abergavennyas.org.uk\/wp-content\/uploads\/2020\/05\/Panet-9_Physics-World.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-3148\" src=\"http:\/\/abergavennyas.org.uk\/wp-content\/uploads\/2020\/05\/Panet-9_Physics-World.jpg\" alt=\"\" width=\"629\" height=\"522\" srcset=\"http:\/\/abergavennyas.org.uk\/wp-content\/uploads\/2020\/05\/Panet-9_Physics-World.jpg 629w, http:\/\/abergavennyas.org.uk\/wp-content\/uploads\/2020\/05\/Panet-9_Physics-World-300x249.jpg 300w, http:\/\/abergavennyas.org.uk\/wp-content\/uploads\/2020\/05\/Panet-9_Physics-World-150x124.jpg 150w, http:\/\/abergavennyas.org.uk\/wp-content\/uploads\/2020\/05\/Panet-9_Physics-World-400x332.jpg 400w\" sizes=\"auto, (max-width: 629px) 100vw, 629px\" \/><\/a><\/p>\n<p>Whilst searches for a conventional \u201cPlanet Nine\u201d have proved unsuccessful so far a report in Physics World, dated 19<sup>th<\/sup> May, ( <strong><a href=\"https:\/\/physicsworld.com\/a\/if-planet-nine-is-a-primordial-black-hole-could-we-detect-it-with-a-fleet-of-tiny-spacecraft\/\">Link<\/a><\/strong> ) looks at the proposal by Edwar Witten, Princeton, to evaluate the suggestion, first made in 2019 by Scholtz, Durham, and Unwin, Chicago, that a small black hole, around 10 times the mass of the Earth, could be stabilising these orbits.&nbsp; This is very small, a black hole the mass of the sun only has a radius of around 3 km (the Schwarzschild radius), the distance from Abergavenny to Govilon.<\/p>\n<p>Witten\u2019s proposal is to launch a fleet of lightweight probes, 100g, in the direction of the presumed Black Hole.&nbsp; To quote the article \u201cHis proposal is a more modest version of the Breakthrough Starshot project ( <strong><a href=\"https:\/\/physicsworld.com\/a\/riding-a-laser-beam-to-alpha-centuri-how-the-sun-pushes-on-the-earth-and-22-kinds-of-space-tape\/\">Link<\/a><\/strong> ) which aims to send ultra-light probes on a 20 year journey to the nearby star Alpha Centauri using an Earth bound laser array\u201d.&nbsp; Witten\u2019s proposal would involve a 10 year journey to 500 AU, well beyond the Kuiper Belt, which is thought to extend to 50 AU and towards the hypothetical Oort Cloud which may start at 2,000 AU.<\/p>\n<p>However, Witten does qualify his proposal, \u201cIt is far from clear that this approach is practical\u2026\u201d<\/p>\n<p>Mike Brown, Caltech, a Planet 9 searcher says \u201cWe\u2019re still looking hard.&nbsp; If we don\u2019t find Planet Nine in any of the dedicated searches, I suspect it will turn up pretty quickly in LSST [the Large Synoptic Survey Telescope\u201d.&nbsp; Read Brown\u2019s Planet 9 hypothesis at ( <strong><a href=\"https:\/\/physicstoday.scitation.org\/doi\/10.1063\/PT.3.4172\">Link<\/a><\/strong> )<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Pluto may have been demoted from planet status back in 2006 but astronomers are still trying to explain the orbits of a number of other Kuiper Belt objects which are in highly elliptical orbits. Whilst searches for a conventional \u201cPlanet Nine\u201d have proved unsuccessful so far a report in Physics World, dated 19th May, ( [&hellip;]<\/p>\n","protected":false},"author":46,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_s2mail":"yes","ngg_post_thumbnail":0,"footnotes":""},"categories":[9],"tags":[],"class_list":["post-3147","post","type-post","status-publish","format-standard","hentry","category-news"],"_links":{"self":[{"href":"http:\/\/abergavennyas.org.uk\/index.php?rest_route=\/wp\/v2\/posts\/3147","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/abergavennyas.org.uk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/abergavennyas.org.uk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/abergavennyas.org.uk\/index.php?rest_route=\/wp\/v2\/users\/46"}],"replies":[{"embeddable":true,"href":"http:\/\/abergavennyas.org.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3147"}],"version-history":[{"count":5,"href":"http:\/\/abergavennyas.org.uk\/index.php?rest_route=\/wp\/v2\/posts\/3147\/revisions"}],"predecessor-version":[{"id":3153,"href":"http:\/\/abergavennyas.org.uk\/index.php?rest_route=\/wp\/v2\/posts\/3147\/revisions\/3153"}],"wp:attachment":[{"href":"http:\/\/abergavennyas.org.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3147"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/abergavennyas.org.uk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3147"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/abergavennyas.org.uk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3147"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}