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Helium is the second element on the [[periodic table of elements]]. It is also the second most abundant element in the universe, after [[hydrogen]]. Helium is created by [[nuclear fusion]] in the center of stars.  

Helium is the second element on the [[periodic table of elements]]. It is also the second most abundant element in the universe, after [[hydrogen]]. Helium is created by [[nuclear fusion]] in the center of stars.  

Helium has an interesting history; during the nineteenth century, one of the things some scientists declared to be "impossible"<ref>[http://www.astrophysical.org/astrophysics.php Astrophysical.org]</ref> was the determination of the chemical makeup of the stars. Then spectroscopy was developed, and the composition of the stars became known in great detail. Helium, in particular, was discovered in the Sun (as an unknown element) ''before'' it was discovered on the Earth. It was first found in natural gas in 1905 at the University of [[Kansas]]. <ref>http://www.news.ku.edu/2000/00N/AprNews/Apr7/bailey.html</ref> It was, accordingly, named after ''helios,'' the Greek for the Sun.

Helium has an interesting history; during the nineteenth century, one of the things some scientists declared to be "impossible"<ref>[http://www.astrophysical.org/astrophysics.php Astrophysical.org]</ref> was the determination of the chemical makeup of the stars. Then spectroscopy was developed, and the composition of the stars became known in great detail. Helium, in particular, was discovered in the Sun (as an unknown element) ''before'' it was discovered on the Earth. It was first found in natural gas in 1905 at the [[University of Kansas]]. <ref>http://www.news.ku.edu/2000/00N/AprNews/Apr7/bailey.html</ref> It was, accordingly, named after ''helios,'' the Greek for the Sun.

==Notes and references==

==Notes and references==

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[[Category:Elements]]

[[Category:Elements]]