Editing Planetary core (section)

====Earth–Moon system====
The [[giant impact hypothesis]] states that an impact between a theoretical Mars-sized planet [[Theia (hypothetical planet)|Theia]] and the early Earth formed the modern Earth and Moon.<ref name="Halliday and N. 2000">{{cite journal |last1=Halliday |last2=N. |first2=Alex |title=Terrestrial accretion rates and the origin of the Moon |journal=Earth and Planetary Science Letters |publisher=Science |volume=176 |issue=1 |date=February 2000 |pages=17–30 |doi=10.1016/s0012-821x(99)00317-9 |bibcode=2000E&PSL.176...17H}}</ref> During this impact the majority of the iron from Theia and the Earth became incorporated into the Earth's core.<ref name="Seti Institute 2012">{{Cite web |date=2012 |title=A new Model for the Origin of the Moon |url=http://www.seti.org/node/1458 |url-status=dead |archive-url=https://web.archive.org/web/20121021013405/http://www.seti.org/node/1458 |archive-date=21 October 2012 |publisher=[[SETI Institute]]}}</ref>