Spin › Forums › Spectroscopy › Solar spectrum › Spin 18 June 2018 at 5:00 pm #579614 Robin LeadbeaterParticipant Hi Jack, The two Na D lines are from the two different spin levels. (3s to 3p1/2 and 3p3/2 in absorption) There probably is Zeeman splitting of the lines as well but this will be very small in the solar magnetic field. Cheers Robin
