Editing History of science (section)

===Space exploration===
In 1925, [[Cecilia Payne-Gaposchkin]] determined that stars were composed mostly of hydrogen and helium.<ref>Erik Gregersen. "Cecilia Payne-Gaposchkin | American Astronomer." Encyclopædia Britannica, https://www.britannica.com/biography/Cecilia-Payne-Gaposchkin {{Webarchive|url=https://web.archive.org/web/20181008214403/https://www.britannica.com/biography/Cecilia-Payne-Gaposchkin |date=8 October 2018 }}.</ref> She was dissuaded by astronomer [[Henry Norris Russell]] from publishing this finding in her PhD thesis because of the widely held belief that stars had the same composition as the Earth.<ref name="newn.cam.ac.uk">Rachael Padman. "Cecilia Payne-Gaposchkin (1900–1979)." Newnham College Biographies, 2004, http://www.newn.cam.ac.uk/about/history/biographies/ {{Webarchive|url=https://web.archive.org/web/20170325225822/http://www.newn.cam.ac.uk/about/history/biographies/ |date=25 March 2017 }}.</ref> However, four years later, in 1929, [[Henry Norris Russell]] came to the same conclusion through different reasoning and the discovery was eventually accepted.<ref name="newn.cam.ac.uk"/>

In 1987, supernova [[SN 1987A]] was observed by astronomers on Earth both visually, and in a triumph for [[neutrino astronomy]], by the solar neutrino detectors at [[Kamiokande]]. But the solar neutrino flux was [[solar neutrino problem|a fraction of its theoretically expected value]]. This discrepancy forced a change in some values in the [[standard model]] for [[particle physics]].