How Much Uranium is in the Solar System?

August 08, 2009

We don't know the composition of the asteroids or the objects in the Oort comet cloud or the Kuiper belt in great detail. One theory of solar system formation is that there are more metals in the inner solar system. That would mean most of the uranium is Mars, Mercury, Earth Venus and asteroid belt.

There is an estimated 40 trillion tons of Uranium and 120 trillion tons of thorium in the Earth's crust. Most of that Uranium is concentrated in the continental crust. The mantel has lower concentration of uranium, but there is a lot more mantel and mantel recycles out to crust.

The solar heavy-element abundances described above are typically measured both using spectroscopy of the Sun's photosphere and by measuring abundances in meteorites that have never been heated to melting temperatures. These meteorites are thought to retain the composition of the protostellar Sun and thus not affected by settling of heavy elements. The two methods generally agree well.

Meteors tend to only have 0.008 ppm uranium

The Sun is 332,830 earth masses. So if the Sun was 8 ppb (parts per billion) uranium, then 0.27% of an earth mass of uranium in the Sun.

The National Physics laboratory (UK) has an estimate of the amount of all elements in the sun, solar system, meteorites, crust and ocean

Full article here:

http://nextbigfuture.com/2009/08/how-much-uranium-is-in-solar-system.html