Hydrogen, by far the commonest element in the cosmos, is followed by helium and more distantly by heavier elements such as oxygen and carbon. For every 10,000,000 atoms of hydrogen, there are approximately 1,400,000 of helium, 6,800 of oxygen, 3,000 of carbon, 2,800 of neon, 910 of nitrogen, and 290 of magnesium.