Spectral lines: From Jennys to jets

Airplanes do not pervade our lives to the same extent as do other modern developments, as for example automobiles. Yet the impact planes have had on our modern culture, despite their short history, is enormous. For most of us the use of commercial airlines to routinely attend business meetings has become a fact of life, and the number of our neighbors and acquaintances who have flown for business or pleasure has increased dramatically in the last decade.