Cosmological lithium problem: Difference between revisions

Revision as of 23:16, 26 May 2021

Revision as of 20:09, 7 August 2021

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[[Image:SolarSystemAbundances.svg|thumb|center|800px|Abundances of the chemical elements in the Solar System. Hydrogen and helium are most common, residuals within the paradigm of the Big Bang.<ref>{{cite book |last1=Stiavelli |first1=M. |year=2009 |title=From First Light to Reionization the End of the Dark Ages |url=https://books.google.com/books?id=iCLNBElRTS4C&pg=PA8 |page=8 |publisher=[[Wiley-VCH]] |___location=Weinheim, Germany |isbn=9783527627370|bibcode=2009fflr.book.....S }}</ref> Li, Be and B are rare because they are poorly synthesized in the Big Bang and also in stars; the main source of these elements is [[cosmic ray spallation]].]]

Older stars seem to have less lithium than they should, and some younger stars have much more.<ref name="MWoo">{{cite web|title=The Cosmic Explosions That Made the Universe|url=http://www.bbc.com/earth/story/20170220-the-cosmic-explosions-that-made-the-universe|last=Woo|first=M.|date=21 Feb 2017|website=earth|publisher=BBC|url-status=live|archiveurl=https://web.archive.org/web/20170221214442/http://www.bbc.com/earth/story/20170220-the-cosmic-explosions-that-made-the-universe|archivedate=21 February 2017|access-date=21 Feb 2017|quote=A mysterious cosmic factory is producing lithium. Scientists are now getting closer at finding out where it comes from|df=dmy-all}}</ref> The lack of lithium in older stars is apparently caused by the "mixing" of lithium into the interior of stars, where it is destroyed,<ref name=cld>{{Cite news |url=http://www.universetoday.com/476/why-old-stars-seem-to-lack-lithium/ |title=Why Old Stars Seem to Lack Lithium |date=16 August 2006 |last=Cain |first=F.Fraser |url-status=live |archiveurl=https://web.archive.org/web/20160604044857/http://www.universetoday.com/476/why-old-stars-seem-to-lack-lithium/ |archivedate=4 June 2016 |df=dmy-all }}</ref> while lithium is produced in younger stars. Though it [[lithium burning|transmutes]] into two atoms of [[helium]] due to collision with a [[proton]] at temperatures above 2.4 million degrees Celsius (most stars easily attain this temperature in their interiors), lithium is more abundant than current computations would predict in later-generation stars.<ref name=emsley/><ref name="Cain">{{cite web|url=http://www.universetoday.com/24593/brown-dwarf/|archiveurl=https://web.archive.org/web/20110225032434/http://www.universetoday.com/24593/brown-dwarf/|archivedate=25 February 2011|title=Brown Dwarf |accessdate=17 November 2009 |last=Cain |first=F.Fraser |publisher=Universe Today}}</ref>

[[File:Nova Centauri 2013 ESO.jpg|thumb|[[Nova Centauri 2013]] is the first in which evidence of lithium has been found.<ref>{{cite web|title=First Detection of Lithium from an Exploding Star|url=http://www.eso.org/public/news/eso1531/|accessdate=29 July 2015|url-status=dead|archiveurl=https://web.archive.org/web/20150801001700/http://www.eso.org/public/news/eso1531/|archivedate=1 August 2015|df=dmy-all}}</ref>]]