Estimated Abundance of Elements (in relative atomic %)
Earth		Earth's crust		Earth's Atmosphere
Oxygen	50	Oxygen	47	Nitrogen	78
Iron	17	Silicon	28	Oxygen	21
Silicon	14	Aluminium	8.1	Argon	0.93
Magnesium	14	Iron	5	Carbon	0.03
Sulphur	1.6	Calcium	3.6	Neon	0.0018
Nickel	1.1	Sodium	2.8	Helium	0.00052
Aluminium	1.1	Potassium	2.6
Universe		Sun		Humans
Hydrogen	92.47	Hydrogen	90.99	Hydrogen	61
Helium	7.4	Helium	8.87	Oxygen	26
Oxygen	0.06	Oxygen	0.078	Carbon	10.5
Carbon	0.03	Carbon	0.033	Nitrogen	2.4
Nitrogen	0.01	Neon	0.011	Calcium	0.23
Neon	0.01	Nitrogen	0.01	Phosphorus	0.13
Others	0.01	Magnesium	0.004	Sulphur	0.13
	Earth	Earth's crust
Oxygen	50	47
Iron	17	5
Silicon	14	28
Magnesium	14	0.1
Sulphur	1.6	0.1
Nickel	1.1	0.1
Aluminium	1.1	8.1
Calcium	0.1	3.6
Sodium	0.1	2.8
Potassium	0.1	2.6