While observing a solar eclipse in 1868, astronomer Pierre Janssen noticed bright yellow lines in the Sun's chromosphere. He concluded that the chromosphere was gaseous and that it could be studied in the absence of an e... More »

The discovery of helium on Earth was made in the United Kingdom by Scottish chemist Sir William Ramsay in 1895. However, the element was first discovered on the sun by French astronomer Pierre Janssen. More »

Helium was originally discovered on the sun by a French astronomer named Pierre-Jules-Cesar Janssen. Janssen made his discovery when he observed a yellow line within the sun's spectrum in 1868 during a solar eclipse. More »

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A solar eclipse occurs when the Moon passes between the Sun and Earth so that the Moon's shadow falls on the Earth. A lunar eclipse occurs when the Earth passes between the Sun and Moon and the Sun casts the Earth's shad... More »

During a solar eclipse, the period of totality, which is when the Sun is completely covered, can last as long as seven minutes and 31 seconds, but most end sooner. During this brief phenomenon, the sun's corona can be se... More »

As of 2015, all modern airships, party balloons and many weather balloons are inflated using helium. Helium is a lighter-than-air gas that is relatively inert, especially in comparison to hydrogen, another gas that is so... More »

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At today's rate in 2015, the world will run out of helium in 25 to 30 years, and that means much more than losing birthday balloons. Helium is critical to operating medical equipment, electronics and even NASA technology... More »

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