Helium is named after the sun, "helios". So, it was discovered on the sun first. Why was it discovered on the sun before we knew about it here on Earth? Do we get our helium from the sun?
The book will talk about first detecting helium in a total solar eclipse and measuring the spectral lines of helium. I don't mean that.
Why were the first spectral lines detected on the sun, and not here on the Earth?
It is in part an accident and in part due to the inertness of helium and the resulting absence of helium in the multitude of chemicals forming naturally found minerals and liquids (see web page http://en.wikipedia.org/wiki/Helium for various facts on Helium and page http://en.wikipedia.org/wiki/Discovery_of_the_chemical_elements ...
Helium and spectral lines on the sun are examined.