9781422279465

Helium: CHAPTER 1

Discovery and History

H elium is the second most abundant element in the universe. Scientists estimate that 73 percent of the universe is hydrogen, 25 percent is helium, and the other 2 percent is made up of all the other elements. The same proportions of elements exist in our Sun as well. So it isn’t much of a surprise that helium was discovered on the Sun in 1868. And yet, it wasn’t discovered on Earth until the 1880s. Why did it take so long? For one reason, helium exists in Earth’s atmosphere at very low levels. It is estimated that in Earth’s atmosphere, only 1 out of every 200,000 particles is helium. It can be found in other places on Earth, too, but it turns out, people just weren’t looking in the right places.

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