Letter from Thomas Gold to Dr Franklin D Martin, Program Manager, Advanced Programs and Technology, Code SM, NASA Headquarters, Washington DC Concernign the announcement of Opportunity No. 8. States this letter is to be added to Gold's letter of 9 April on the same subject. States they would also have great interest in measurements of electrons in the energy range from 150 eV to 2000 eV. Gives the two separate reasons for this. 10 April 1975