|MadSci Network: Physics
Well, most of the universe (90% by number) is made up of Hydrogen atoms (the simplest atom, just a proton and an electron). So I'll simplify things by working out the equvalent number of hydrogen atoms for each object. The actual number of atoms will always be somewhat less, since all other atoms are heavier. For the Sun and Solar System, using the actual compostion will reduce the number by about 20%. For the Earth, the actual number will be...mmmm...say 40 times less, since the earth is mainly made up of fairly heavy atoms. For the universe as a whole, I have given a LOWER LIMIT for the number of atoms. We don't yet really know what the mass of the universe is, nor just how may atoms are in it. I have given the results both in scientific notation, for example 1.2E+57 atoms in the Sun, meaning 1.2 multiplied by 1 with 57 zeros after it, and in "normal" format. Since in the "normal" forma these numbers get rather long, I have placed them on their own lines -- still they may "wrap" around onto more than one line when you view them on the Web. Object Mass (kg) Number of Atoms (assuming all Hydrogen) Hydrogen atom 1.67E-27 1 1 Earth 6.42E+23 3.8E+50 384,359,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 Sun 1.99E+30 1.2E+57 1,191,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,0 00 Solar System 1.99E+30 1.2E+57 1,192,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,0 00 Universe 1.99E+52 1.2E+79 12,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000, 000,000,000,000,000,000,000,000
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