All the gold on the earth is thought to have come from asteroids. All the gold that was present when the Earth was formed sank to the core a long time ago.[1]<p>The moon is thought contain Helium 3 which can be used for fusion reactors.[2]<p>[1]<a href="http:&#x2F;&#x2F;www.sciencedaily.com&#x2F;releases&#x2F;2011&#x2F;09&#x2F;110907132044.htm" rel="nofollow">http:&#x2F;&#x2F;www.sciencedaily.com&#x2F;releases&#x2F;2011&#x2F;09&#x2F;110907132044.ht...</a><p>[2]<a href="http:&#x2F;&#x2F;www.esa.int&#x2F;Our_Activities&#x2F;Preparing_for_the_Future&#x2F;Space_for_Earth&#x2F;Energy&#x2F;Helium-3_mining_on_the_lunar_surface" rel="nofollow">http:&#x2F;&#x2F;www.esa.int&#x2F;Our_Activities&#x2F;Preparing_for_the_Future&#x2F;S...</a>