The first evidence of helium was observed on August 18, 1868 as a bright yellow line with a wavelength of 587.49 nanometers in the spectrum of the chromosphere of the Sun. The line was detected by French astronomer Jules Janssen during a total solar eclipse in Guntur, India.
On October 20, 1868, English astronomer Norman Lockyer observed a yellow line in the solar spectrum, which he named the D3 Fraunhofer line because it was near the known D1 and D2 lines of sodium. He concluded that it was caused by an element in the Sun unknown on Earth. Lockyer and English chemist Edward Frankland named the element with the Greek word for the Sun, (helios).
In 1882, Italian physicist Luigi Palmieri detected helium on Earth, for the first time, through its D3 spectral line, when he analyzed the lava of Mount Vesuvius.
On March 26, 1895, Scottish chemist Sir William Ramsay isolated helium on Earth by treating the mineral cleveite (a variety of uraninite with at least 10% rare earth elements) with mineral acids. Ramsay was looking for argon but, after separating nitrogen and oxygen from the gas liberated by sulfuric acid, he noticed a bright yellow line that matched the D3 line observed in the spectrum of the Sun.
convection currents discovery date
After the airship Hindenburg II burned up because of the Hydrogen gas it used. Over 200 people were killed. After this, people realized that Hydrogen was too dangerous to be used. So, they started using Helium, an inert gas.
1984, Darmstadt (Germany).
Jupiter was discovered by Galileo on January 7, 1610.
Uranus was discovered on March 13, 1781 by William Herschel.
Because helium was discovered by spectral methods in the Sun.
The discovery and date of aluminum
what is the Discovery Date for mercury? please someone tell me!!!!!!!!!!!
Saturn has been visible as long as mankind can remember, so it does not have a discovery date.
1774
1808
1965
1782
1518 if you think of "discovery" as being found by Europeans.
convection currents discovery date
1898
The uses of fire.